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Question 1
Incorrect
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Which one of the following statements regarding digoxin is accurate?
Your Answer: It has a short half-life
Correct Answer: Toxicity can occur in patients with digoxin levels in the therapeutic range
Explanation:Understanding Digoxin and Its Toxicity
Digoxin is a medication used for rate control in atrial fibrillation and for improving symptoms in heart failure patients. It works by decreasing conduction through the atrioventricular node and increasing the force of cardiac muscle contraction. However, it has a narrow therapeutic index and requires monitoring for toxicity.
Toxicity may occur even when the digoxin concentration is within the therapeutic range. Symptoms of toxicity include lethargy, nausea, vomiting, anorexia, confusion, yellow-green vision, arrhythmias, and gynaecomastia. Hypokalaemia is a classic precipitating factor, as it allows digoxin to more easily bind to the ATPase pump and increase its inhibitory effects. Other factors that may contribute to toxicity include increasing age, renal failure, myocardial ischaemia, electrolyte imbalances, hypoalbuminaemia, hypothermia, hypothyroidism, and certain medications such as amiodarone, quinidine, and verapamil.
Management of digoxin toxicity involves the use of Digibind, correction of arrhythmias, and monitoring of potassium levels. It is important to recognize the potential for toxicity and monitor patients accordingly to prevent adverse outcomes.
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This question is part of the following fields:
- Pharmacology
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Question 2
Incorrect
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A 50-year-old man is recuperating from an appendectomy in the surgical ward. He is administered an antiemetic to alleviate post-anaesthesia nausea. After two hours, he is discovered contorting in his bed, incapable of communicating. His limbs are stiff and inflexible.
What drug would you prescribe to remedy his condition?Your Answer: Trazodone
Correct Answer: Procyclidine
Explanation:Extrapyramidal Side-Effects and Antiemetics
Extrapyramidal side-effects (EPS) can occur with certain medications, including antiemetics. EPS can cause acute dystonia, which presents as involuntary muscle contractions and spasms. The first-line treatment for acute dystonia is procyclidine, given by slow intravenous injection. The dose usually takes 5-10 minutes to be effective, but relief may take up to 30 minutes.
Trazodone is not an antiemetic but an antipsychotic that can cause EPS. Metoclopramide is an antiemetic that can induce EPS, making it important to monitor patients for acute dystonia. Ondansetron can also cause EPS, but it is less common than with metoclopramide and haloperidol. Domperidone is another antiemetic that can cause EPS and should be used with caution in patients at risk for acute dystonia.
In summary, EPS is a potential side-effect of some antiemetics, and procyclidine is the first-line treatment for acute dystonia. Healthcare providers should monitor patients for EPS and adjust treatment as necessary to prevent or manage this condition.
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This question is part of the following fields:
- Pharmacology
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Question 3
Incorrect
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A 62-year-old woman presents to the clinic with ongoing vaginal bleeding for the past six to eight weeks. She had undergone menopause a decade ago and has been on tamoxifen since being diagnosed with breast cancer four years ago. What is the most concerning diagnosis in this case?
Your Answer: Ovarian cancer
Correct Answer: Endometrial cancer
Explanation:Tamoxifen: A Selective Estrogen Receptor Modulator for Breast Cancer
Tamoxifen is a medication that selectively modulates estrogen receptors and has been found to reduce the risk of breast cancer recurrence in women. Although it is associated with potential adverse effects such as increased risk of endometrial cancer, raised triglycerides, and venous thromboembolism, the benefits of tamoxifen in reducing the risk of breast cancer recurrence outweigh these risks. There is no evidence of increased risk for other types of tumors. However, patients who have been treated with tamoxifen and report abnormal bleeding should be investigated to rule out the possibility of an endometrial neoplasm. Overall, tamoxifen is a valuable medication for reducing the risk of breast cancer recurrence in women.
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This question is part of the following fields:
- Pharmacology
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Question 4
Incorrect
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A 63-year-old man who is receiving treatment for alcoholism presents with a week-long history of pins and needles in his right arm. He continues to consume over 20 units of alcohol per day and is taking disulfiram and citalopram. On examination, there are no signs of weakness, abnormal movements, or changes in tone, and his sensation is intact in all dermatomes. A blood test reveals a clinically significant result of Mg2+ 0.5 mmol/L (0.65 - 1.05). The patient is prescribed oral magnesium sulfate, and his doctor informs him of a potential side effect of the medication. What side effect is the patient likely to be warned about?
Your Answer: Constipation
Correct Answer: Diarrhoea
Explanation:Severe diarrhoea is the main side effect that limits the dosage of magnesium salts. Hypomagnesaemia can cause symptoms similar to hypokalemia, such as paraesthesia. Heavy alcohol consumption can lead to magnesium loss from tissues and increased urinary magnesium loss. Oral magnesium sulfate is the treatment for hypomagnesaemia above 0.4 mmol/L, while intravenous magnesium sulfate is used for levels below 0.4 mmol/L. Although constipation resulting from paralytic ileus is a rare side effect of oral magnesium salts, severe diarrhoea is the more common clinical presentation. Loss of appetite is not a known side effect of oral magnesium salts, and nausea is only seen in cases of magnesium salt overdose, not at therapeutic levels.
Understanding Hypomagnesaemia: Causes, Symptoms, and Treatment
Hypomagnesaemia is a condition characterized by low levels of magnesium in the blood. There are several causes of this condition, including the use of certain drugs such as diuretics and proton pump inhibitors, total parenteral nutrition, and chronic or acute diarrhoea. Alcohol consumption, hypokalaemia, hypercalcaemia, and metabolic disorders like Gitelman’s and Bartter’s can also lead to hypomagnesaemia. The symptoms of this condition may be similar to those of hypocalcaemia, including paraesthesia, tetany, seizures, and arrhythmias.
When the magnesium level drops below 0.4 mmol/L or when there are symptoms of tetany, arrhythmias, or seizures, intravenous magnesium replacement is commonly given. An example regime would be 40 mmol of magnesium sulphate over 24 hours. For magnesium levels above 0.4 mmol/L, oral magnesium salts are prescribed in divided doses of 10-20 mmol per day. However, diarrhoea can occur with oral magnesium salts. It is important to note that hypomagnesaemia can exacerbate digoxin toxicity.
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This question is part of the following fields:
- Pharmacology
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Question 5
Incorrect
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Which agent from the list does not lead to the development of osteoporosis?
Your Answer: Heparin
Correct Answer: Oestrogen
Explanation:Factors Affecting Bone Mass
Long-term use of heparin has been found to decrease bone mass, but low molecular weight heparin may have less of an impact than unfractionated heparin. Methotrexate is not a common cause of osteoporosis, but it can worsen the effects of corticosteroid-induced osteoporosis. On the other hand, estrogen has a protective effect against osteoporosis. Steroids, however, have been shown to reduce osteoblastic and osteoclastic activity, decrease calcium absorption, and increase bone resorption, all of which contribute to the development of osteoporosis. It is important to consider these factors when evaluating the risk of osteoporosis in patients undergoing long-term treatment with these medications.
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This question is part of the following fields:
- Pharmacology
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Question 6
Incorrect
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A 35-year-old woman with bipolar disorder has been consistently taking her medication during pregnancy. During her recent ultrasound, her baby was found to have characteristics linked to spina bifida. Which medication is the most probable cause of this?
Your Answer: Olanzapine
Correct Answer: Sodium valproate
Explanation:The Teratogenic Effects of Certain Medications During Pregnancy
During pregnancy, certain medications can have teratogenic effects on the developing fetus. One such medication is sodium valproate, which is an anticonvulsant and bipolar disorder treatment. Its use during pregnancy is contraindicated due to its association with congenital malformations and neurodevelopmental disorders, such as spina bifida, congenital heart defects, cleft lip, and neonatal bleeding disorders. If sodium valproate must be used during pregnancy, the lowest effective dose should be administered and additional monitoring is required.
Lithium therapy during pregnancy has also been linked to an increased risk of congenital heart disease, stillbirth, and early infant deaths, as well as increased risk of toxicity for both the mother and fetus. Olanzapine, on the other hand, has been found to have the same risk of congenital defects as the general population.
Bupropion has been associated with an increased risk of congenital heart defects if used during pregnancy. However, studies suggest that carbamazepine has one of the lowest rates of teratogenicity when used during pregnancy. It is important for healthcare providers to carefully consider the risks and benefits of medication use during pregnancy and to explore alternative options whenever possible.
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This question is part of the following fields:
- Pharmacology
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Question 7
Incorrect
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What is the correct pairing of a disorder with its treatment?
Your Answer: Atrial fibrillation (AF) and amlodipine
Correct Answer: Systemic lupus erythematosus (SLE) and hydroxychloroquine
Explanation:Common Medical Conditions and their Corresponding Treatments
Systemic lupus erythematosus (SLE) and hydroxychloroquine
Hydroxychloroquine is a medication used to treat SLE and rheumatoid arthritis. It works by blocking toll-like receptor signalling, reducing activation of dendritic cells and the subsequent inflammatory process.Epilepsy and amitriptyline
Amitriptyline is a tricyclic antidepressant used to treat depression and pain. However, it may lower the seizure threshold and aggravate epilepsy.Atrial fibrillation (AF) and amlodipine
Amlodipine is a medication used to treat high blood pressure. It has no anti-arrhythmic activity and is not typically used to treat AF. Other calcium antagonists such as verapamil and diltiazem may be used to treat AF.Type 1 diabetes (T1DM) and gliclazide
Oral hypoglycaemics like gliclazide are ineffective in treating T1DM. Insulin therapy is the mainstay of treatment for T1DM.Hepatitis C and lamivudine
Hepatitis C is treated with direct acting antivirals like ledipasvir/sofosbuvir. Lamivudine is not typically used to treat Hepatitis C.Medications and their Corresponding Medical Conditions
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This question is part of the following fields:
- Pharmacology
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Question 8
Correct
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A new arthritis medication is being developed that is described as having a higher potency than current drugs of that class.
What is meant by potency?Your Answer: The amount required to produce an effect of given intensity
Explanation:Understanding Pharmacological Terms: Potency, Metabolism, Efficacy, Absorption, and Therapeutic Window
Pharmacological terms can be confusing, but understanding them is crucial for effective drug development and use. Potency refers to the amount of a drug required to produce a given effect, while metabolism is the rate at which a drug is converted to its metabolites. Efficacy is the maximal response a drug can produce when all receptors are occupied, and absorption is the rate at which a drug enters the bloodstream. Finally, the therapeutic window is the dose range at which a drug is effective and safe. Doses below the minimum are ineffective, while doses above the maximum are toxic. By understanding these terms, we can better evaluate the potential of drugs and use them safely and effectively.
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This question is part of the following fields:
- Pharmacology
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Question 9
Incorrect
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A 25-year-old female presents to the hospital with complaints of abdominal pain. During her evaluation, a pregnancy test is performed and unexpectedly comes back positive despite the patient claiming to have been taking her combined oral contraceptive pill as directed. Upon further investigation, it is discovered that she has recently started a medication that may have played a role in her pregnancy. What is the most likely medication that she has recently begun taking?
Your Answer: Ciprofloxacin
Correct Answer: Carbamazepine
Explanation:Carbamazepine induces the P450 enzyme. This enzyme system includes CYP3A4, which metabolizes ethinylestradiol, a component of the combined oral contraceptive (COC) pill. Induction of P450 enzymes accelerates the breakdown of ethinylestradiol, reducing the effectiveness of the COC pill. On the other hand, ciprofloxacin and omeprazole inhibit P450 enzymes, slowing down the breakdown of P450 enzyme substrates. Propranolol is a P450 enzyme substrate, but it does not affect the efficacy of the enzyme system.
P450 Enzyme System and its Inducers and Inhibitors
The P450 enzyme system is responsible for metabolizing drugs in the body. Induction of this system usually requires prolonged exposure to the inducing drug, unlike P450 inhibitors, which have rapid effects. Some drugs that induce the P450 system include antiepileptics like phenytoin and carbamazepine, barbiturates such as phenobarbitone, rifampicin, St John’s Wort, chronic alcohol intake, griseofulvin, and smoking, which affects CYP1A2 and is the reason why smokers require more aminophylline.
On the other hand, some drugs inhibit the P450 system, including antibiotics like ciprofloxacin and erythromycin, isoniazid, cimetidine, omeprazole, amiodarone, allopurinol, imidazoles such as ketoconazole and fluconazole, SSRIs like fluoxetine and sertraline, ritonavir, sodium valproate, and acute alcohol intake. It is important to be aware of these inducers and inhibitors as they can affect the metabolism and efficacy of drugs in the body. Proper dosing and monitoring can help ensure safe and effective treatment.
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This question is part of the following fields:
- Pharmacology
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Question 10
Correct
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A 70-year-old man is admitted to an acute psychiatric unit with sudden onset of agitation and psychosis. He has a history of schizophrenia with a fluctuating course. To alleviate his symptoms, he is given a one-time intramuscular injection of 50 mg chlorpromazine. What is the primary pharmacological effect of chlorpromazine in managing psychosis?
Your Answer: Dopaminergic blockade in the mesolimbic system
Explanation:Chlorpromazine is a typical antipsychotic drug that acts on many neurotransmitter systems, but it’s antipsychotic properties come from its action on dopaminergic neurotransmission in the mesolimbic system. However, blocking dopamine transmission can also cause extrapyramidal side effects of movement and hyperprolactinemia. The drug’s anticholinergic actions cause dry mouth, urinary retention, palpitations, tachycardia, abnormal dreams, and hypotension. Inhibition of serotonergic neurotransmission can attenuate the anticholinergic side effects and inhibit aggressive tendencies and anxiety.
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This question is part of the following fields:
- Pharmacology
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Question 11
Incorrect
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What is the mode of action of cholestyramine in the management of hyperlipidemia?
Your Answer: Reduced cholesterol synthesis through inhibition of the enzyme HMG CoA reductase
Correct Answer: Prevent cholesterol absorption from the intestine
Explanation:Limitations of Bile Acid Sequestrants
Bile acid sequestrants are medications that are used to lower cholesterol levels in the body. However, their use is limited due to the many side effects that they can cause. These medications are generally unpleasant to take and patients often do not tolerate them well. They are suitable for use in patients who are intolerant to statins or who have had serious adverse effects from statins. They can also be used in combination with statins in patients with markedly elevated LDL cholesterol levels.
The main side effects of bile acid sequestrants include gallstones, constipation, bloating, reflux disease, abdominal discomfort, reduced absorption of lipids leading to greasy unpleasant stools, reduced absorption of certain vitamins including vitamin D and folate, and reduced absorption of certain drugs, including warfarin and digoxin. These side effects can limit the use of bile acid sequestrants in many patients. Therefore, it is important to carefully consider the risks and benefits of these medications before prescribing them to patients.
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This question is part of the following fields:
- Pharmacology
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Question 12
Incorrect
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What is the most appropriate mechanism to describe the action of simvastatin?
Your Answer: Inhibits cholesterol absorption
Correct Answer: Decreases hepatic cholesterol synthesis
Explanation:How Statins Work to Lower Cholesterol
Cholesterol is primarily produced within the body through the HMG-CoA reductase pathway, which is responsible for manufacturing around 1000 mg of cholesterol per day via carbohydrate metabolism. However, statins work by competitively inhibiting HMG-CoA reductase, which is the first enzyme in this pathway. By doing so, statins can effectively lower circulating cholesterol levels. For those looking to learn more about statins and other lipid-lowering medicines, Patient.info offers additional resources and information.
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This question is part of the following fields:
- Pharmacology
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Question 13
Incorrect
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A 65-year old man presents to his primary care physician with complaints of increasing fatigue. He reports consuming 4-6 units of alcohol daily and has been on medication for a chronic medical condition for the past year. Upon examination, he appears to be in good health and well-nourished. Laboratory tests reveal an elevated gamma glutamyl transpeptidase and a decreased alkaline phosphatase (ALP). Which medication is most likely responsible for these abnormal blood results?
Your Answer: Insulin
Correct Answer: Carbamazepine
Explanation:Common Medications and Their Side Effects
Carbamazepine, a sodium channel blocker, is commonly used to treat epilepsy, trigeminal neuralgia, diabetic neuropathy, acute alcohol withdrawal, and bipolar disorder. However, it can cause drowsiness, fatigue, agranulocytosis, Stevens-Johnson syndrome, and hepatic toxicity. Regular monitoring of carbamazepine serum levels and liver function tests is necessary.
Gentamicin, used to treat bacterial infections, can cause renal and ototoxicity but not liver toxicity.
Amlodipine, a calcium channel blocker, can cause flushing, headaches, and peripheral edema.
Insulin, used to treat diabetes, can cause hypoglycemia, lipodystrophy, skin injection site reactions, and edema.
Bisoprolol, a beta-blocker, can cause bradycardia, heart failure, depression, abdominal discomfort, dizziness, and fatigue. However, it is not associated with liver dysfunction.
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This question is part of the following fields:
- Pharmacology
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Question 14
Correct
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Samantha is a 67-year-old woman who presents with skin changes on her left lower leg. Upon examination, Samantha has a low-grade fever and the left lower leg is erythematosus, mildly swollen, and warm to the touch. The diagnosis is cellulitis, and due to Samantha's penicillin allergy, a course of oral clarithromycin is prescribed.
One week later, Samantha returns with new palpitations. What potential ECG side effect can be associated with this antibiotic?Your Answer: Prolonged QT interval
Explanation:Macrolides have the potential to cause QT interval prolongation, which is a known side effect. Additionally, palpitations may occur as an uncommon side effect of macrolides. A shortened PR interval may indicate pre-excitation or an AV nodal (junctional) rhythm, while a prolonged PR interval suggests first-degree AV block. Prominent P waves are typically caused by right atrial enlargement, which can be due to various conditions such as chronic lung disease, tricuspid stenosis, congenital heart disease, or primary pulmonary hypertension.
Macrolides: Antibiotics that Inhibit Bacterial Protein Synthesis
Macrolides are a class of antibiotics that include erythromycin, clarithromycin, and azithromycin. They work by blocking translocation, which inhibits bacterial protein synthesis. While they are generally considered bacteriostatic, their effectiveness can vary depending on the dose and type of organism being treated.
Resistance to macrolides can occur through post-transcriptional methylation of the 23S bacterial ribosomal RNA. Adverse effects of macrolides include prolongation of the QT interval and gastrointestinal side-effects, with nausea being less common with clarithromycin than erythromycin. Cholestatic jaundice is also a potential risk, although using erythromycin stearate may reduce this risk. Additionally, macrolides are known to inhibit the cytochrome P450 isoenzyme CYP3A4, which can cause interactions with other medications. For example, taking macrolides concurrently with statins significantly increases the risk of myopathy and rhabdomyolysis. Azithromycin is also associated with hearing loss and tinnitus.
Overall, macrolides are a useful class of antibiotics that can effectively treat bacterial infections. However, it is important to be aware of their potential adverse effects and interactions with other medications.
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This question is part of the following fields:
- Pharmacology
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Question 15
Correct
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Which of the following drugs does not inhibit cytochrome P450?
Your Answer: Clopidogrel
Explanation:P450 Enzyme System and its Inducers and Inhibitors
The P450 enzyme system is responsible for metabolizing drugs in the body. Induction of this system usually requires prolonged exposure to the inducing drug, unlike P450 inhibitors, which have rapid effects. Some drugs that induce the P450 system include antiepileptics like phenytoin and carbamazepine, barbiturates such as phenobarbitone, rifampicin, St John’s Wort, chronic alcohol intake, griseofulvin, and smoking, which affects CYP1A2 and is the reason why smokers require more aminophylline.
On the other hand, some drugs inhibit the P450 system, including antibiotics like ciprofloxacin and erythromycin, isoniazid, cimetidine, omeprazole, amiodarone, allopurinol, imidazoles such as ketoconazole and fluconazole, SSRIs like fluoxetine and sertraline, ritonavir, sodium valproate, and acute alcohol intake. It is important to be aware of these inducers and inhibitors as they can affect the metabolism and efficacy of drugs in the body. Proper dosing and monitoring can help ensure safe and effective treatment.
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This question is part of the following fields:
- Pharmacology
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Question 16
Incorrect
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A 55-year-old patient presents with complaints of dyspnea upon exertion. A chest X-ray reveals fibrosis, and the patient reports increasing fatigue and malaise with a pale appearance. Further testing shows an elevated thyroid-stimulating hormone (TSH) level. What medication is this patient currently taking?
Your Answer: Quinidine
Correct Answer: Amiodarone
Explanation:Anti-Arrhythmic Medications: Mechanisms and Side-Effects
Amiodarone, Flecainide, Lidocaine, Procainamide, and Quinidine are all anti-arrhythmic medications used in the treatment of various types of arrhythmias. Each medication has a unique mechanism of action and associated side-effects.
Amiodarone is a class III anti-arrhythmic agent that prolongs the repolarisation phase by blocking potassium efflux. It can cause thyroid dysfunction, pulmonary fibrosis, bradycardia, and other side-effects.
Flecainide is a class Ic sodium channel blocker that slows conduction of the electrical impulse in the heart. It can cause oedema, dyspnoea, visual disturbances, and other side-effects.
Lidocaine is a class Ib anti-arrhythmic agent that shortens the repolarisation phase by blocking Na channels. It can cause drowsiness, respiratory failure, and other side-effects.
Procainamide is a class Ia anti-arrhythmic medication that prolongs the repolarisation phase. It can cause bradycardia, hypotension, and shock. Prolonged use has been associated with the development of systemic lupus erythematosus.
Quinidine is a class Ia anti-arrhythmic medication that prolongs the repolarisation phase and can cause torsades de pointe. It can also lead to thrombocytopenia, myasthenia gravis, and other side-effects.
In conclusion, each anti-arrhythmic medication has its own unique mechanism of action and associated side-effects. It is important to carefully consider the risks and benefits of each medication before prescribing it to a patient.
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This question is part of the following fields:
- Pharmacology
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Question 17
Correct
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A 70-year-old man is prescribed amiodarone for atrial fibrillation. What set of tests should the GP conduct on this patient as a baseline?
Your Answer: Liver function tests (LFTs), urea and electrolytes (U&Es), thyroid function tests (TFTs) and chest X-ray
Explanation:Amiodarone is a medication used to treat heart conditions, but it can have significant side effects. Before starting treatment, it is important to establish a baseline thyroid profile, as amiodarone contains iodine that can cause hyper- or hypothyroidism. A baseline chest X-ray is also required and should be repeated annually, as amiodarone can cause toxicity in the lungs. Liver toxicity is common in those on long-term amiodarone therapy, so liver function tests should be done regularly. Respiratory complications such as pneumonitis and pulmonary fibrosis can occur, so further investigation may be needed if patients develop respiratory symptoms. Other tests such as nerve conduction studies and visual field studies are not necessary before starting amiodarone, but LFTs, U&Es, and TFTs should be done due to the potential for liver and thyroid toxicity.
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This question is part of the following fields:
- Pharmacology
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Question 18
Incorrect
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A 75-year-old man with chronic heart failure is prescribed digoxin for atrial fibrillation. The patient expresses anxiety about starting a new medication. What is the recommended frequency for monitoring the levels of this medication?
Your Answer: Weekly
Correct Answer: No regular monitoring needed
Explanation:According to NICE guidelines, routine monitoring of plasma-digoxin concentration is not necessary during maintenance treatment unless there is suspicion of toxicity. Digoxin has a long half-life and is administered once daily for maintenance doses. If toxicity is suspected, digoxin concentrations should be measured within 8 to 12 hours of the last dose. It is important to note that toxicity can occur even when the concentration is within the therapeutic range, and caution should be exercised when prescribing to the elderly who are at increased risk of toxicity. The BNF advises that the likelihood of toxicity increases progressively from 1.5 to 3 mcg/l. Therefore, digoxin levels are not monitored on a weekly, monthly, or quarterly basis, but rather only in cases where toxicity is suspected.
Understanding Digoxin and Its Toxicity
Digoxin is a medication used for rate control in atrial fibrillation and for improving symptoms in heart failure patients. It works by decreasing conduction through the atrioventricular node and increasing the force of cardiac muscle contraction. However, it has a narrow therapeutic index and requires monitoring for toxicity.
Toxicity may occur even when the digoxin concentration is within the therapeutic range. Symptoms of toxicity include lethargy, nausea, vomiting, anorexia, confusion, yellow-green vision, arrhythmias, and gynaecomastia. Hypokalaemia is a classic precipitating factor, as it allows digoxin to more easily bind to the ATPase pump and increase its inhibitory effects. Other factors that may contribute to toxicity include increasing age, renal failure, myocardial ischaemia, electrolyte imbalances, hypoalbuminaemia, hypothermia, hypothyroidism, and certain medications such as amiodarone, quinidine, and verapamil.
Management of digoxin toxicity involves the use of Digibind, correction of arrhythmias, and monitoring of potassium levels. It is important to recognize the potential for toxicity and monitor patients accordingly to prevent adverse outcomes.
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This question is part of the following fields:
- Pharmacology
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Question 19
Incorrect
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A middle-aged man comes into the surgery because he is unhappy with a new drug that he started in the last 2 months. He claims it gives him pain in the middle of his chest and he has felt more bloated recently.
Which one of the following is most likely to account for these symptoms?Your Answer: Omeprazole
Correct Answer: Alendronic acid
Explanation:Possible Causes of Retrosternal Pain and Bloating
Retrosternal pain and bloating can be caused by various factors, including medication side-effects. Among the drugs listed, alendronic acid is the most likely culprit as it commonly causes oesophagitis. To prevent this, it is recommended to take it 30 minutes before food and avoid lying down for 30 minutes after taking it. On the other hand, omeprazole is a proton pump inhibitor used to treat similar symptoms and is unlikely to cause retrosternal pain. Bisoprolol may cause nausea, vomiting, dry mouth, fatigue, and abdominal pain, but not retrosternal pain. Digoxin’s common side-effects are nausea, diarrhoea, fatigue, and skin rashes. Lastly, gabapentin may cause dizziness, drowsiness, weakness, blurred vision, and gastrointestinal upset. It is important to consult a healthcare professional if experiencing any discomfort or adverse reactions to medication.
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This question is part of the following fields:
- Pharmacology
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Question 20
Incorrect
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A 32-year-old man is brought into the Emergency Department from a party with sudden onset chest pain and extreme agitation. His blood pressure is 136/94 mmHg and his pulse rate is 49/min. A collateral history from his partner suggests the use of illicit drugs.
On examination, he has brisk reflexes bilaterally.
An ECG shows QT prolongation and ST elevation in V1-V4.
What is the probable pathophysiology behind this patient's presentation?Your Answer: Platelet activation leading to thrombotic occlusion of the left anterior descending artery
Correct Answer: Spasm of the coronary arteries
Explanation:Myocardial ischaemia can be caused by cocaine-induced coronary artery spasm.
Understanding Cocaine Toxicity
Cocaine is a popular recreational stimulant derived from the coca plant. However, its widespread use has resulted in an increase in cocaine toxicity cases. The drug works by blocking the uptake of dopamine, noradrenaline, and serotonin, leading to a variety of adverse effects.
Cardiovascular effects of cocaine include coronary artery spasm, tachycardia, bradycardia, hypertension, QRS widening, QT prolongation, and aortic dissection. Neurological effects may include seizures, mydriasis, hypertonia, and hyperreflexia. Psychiatric effects such as agitation, psychosis, and hallucinations may also occur. Other complications include ischaemic colitis, hyperthermia, metabolic acidosis, and rhabdomyolysis.
Managing cocaine toxicity involves using benzodiazepines as a first-line treatment for most cocaine-related problems. For chest pain, benzodiazepines and glyceryl trinitrate may be used, and primary percutaneous coronary intervention may be necessary if myocardial infarction develops. Hypertension can be treated with benzodiazepines and sodium nitroprusside. The use of beta-blockers in cocaine-induced cardiovascular problems is controversial, with some experts warning against it due to the risk of unopposed alpha-mediated coronary vasospasm.
In summary, cocaine toxicity can lead to a range of adverse effects, and managing it requires careful consideration of the patient’s symptoms and medical history.
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This question is part of the following fields:
- Pharmacology
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Question 21
Correct
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A 28-year-old male is brought to the emergency department following a car accident that caused severe thoracic injuries. Upon arrival, the patient's pulses cannot be detected and an ECG reveals asystole. CPR is initiated with a chest compression to rescue breath ratio of 30:2. What is the most appropriate next step in managing this patient?
Your Answer: 10ml 1 in 10,000 adrenaline delivered via intravenous (IV) injection
Explanation:Understanding Adrenaline and Its Indications
Adrenaline is a type of sympathomimetic amine that has both alpha and beta adrenergic stimulating properties. It is commonly used in emergency situations such as anaphylaxis and cardiac arrest. For anaphylaxis, the recommended adult life support adrenaline dose is 0.5ml 1:1,000 IM, while for cardiac arrest, it is 10ml 1:10,000 IV or 1ml of 1:1000 IV.
Adrenaline is responsible for the fight or flight response and is released by the adrenal glands. It acts on α 1 and 2, β 1 and 2 receptors, and causes vasoconstriction in the skin and kidneys, resulting in a narrow pulse pressure. It also increases cardiac output and total peripheral resistance, while causing vasodilation in skeletal muscle vessels.
When adrenaline acts on α adrenergic receptors, it inhibits insulin secretion by the pancreas and stimulates glycogenolysis in the liver and muscle. On the other hand, when it acts on β adrenergic receptors, it stimulates glucagon secretion in the pancreas, stimulates ACTH, and stimulates lipolysis by adipose tissue.
In case of accidental injection, the management involves local infiltration of phentolamine. Understanding the indications and actions of adrenaline is crucial in emergency situations, and proper administration can help save lives.
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This question is part of the following fields:
- Pharmacology
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Question 22
Incorrect
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A pharmaceutical company is presently conducting Phase 1-2 trials for Scarozyme, a new drug intended for the treatment of Meniere's disease. The drug's clearance is being evaluated, with the renal system being the primary means of clearance. What factors must be measured to determine the drug's clearance at any given moment?
Your Answer: Glomerular filtration rate, urine flow rate, plasma concentration
Correct Answer: Plasma concentration, urine concentration, urine flow rate
Explanation:Drug Clearance
Drug clearance refers to the rate at which active drugs are removed from the circulation. This process involves both renal excretion and hepatic metabolism, but in practice, clearance is mostly measured by the renal excretion of a drug. The clearance of a drug can vary widely depending on factors such as the drug’s plasma concentration, structure, and distribution. The glomerular filtration rate can also affect drug clearance, but this is not the only determining factor.
The formula for clearance involves multiplying urine concentration and urine volume and dividing the result by plasma concentration. Clearance can follow either zero order kinetics or first order kinetics. In zero order kinetics, the clearance of the drug remains constant regardless of the plasma concentration. In contrast, first order kinetics means that the clearance of the drug is dependent on the plasma concentration. At high plasma concentrations, the drug is cleared more quickly, while at low concentrations, the drug is cleared more slowly. A graph of drug concentration over time following a single dose will show an exponential decay.
In normal physiological conditions, most drugs are cleared by first order kinetics. drug clearance is important in determining the appropriate dosages of drugs and in predicting their effects on the body.
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This question is part of the following fields:
- Pharmacology
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Question 23
Correct
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A 72-year-old male patient arrives in hospital with a hip fracture. His wife mentions that he drinks around two bottles of wine per day. He is prescribed chlordiazepoxide, a benzodiazepine, for alcohol withdrawal.
What is the reason for using this medication in this situation?Your Answer: Alcohol withdrawal leads to gamma-aminobutyric acid (GABA) deficiency; benzodiazepines facilitate GABA-A binding to its receptor
Explanation:A 79-year-old man is brought to see his general practitioner by his daughter who has noticed that he is becoming increasingly forgetful and unsteady on his feet. Unfortunately his daughter does not know anything about his previous medical history or whether he takes any medications. Routine investigations reveal:
Investigation Result Normal Value
Haemoglobin 105 g/l 135–175 g/l
Mean corpuscular value 101 fl 76–98 fl
White cell count 7.2 × 109/l 4–11 × 109/l
Platelets 80 × 109/l 150–400 x 109/
Sodium 132 mmol/l 135–145 mmol/l
Potassium 4.8 mmol/l 3.5–5.0 mmol/l
Urea 1.3 mmol/l 2.5–6.5 mmol/l
Creatine 78 μmol/l 50–120 µmol/l
Random blood sugar 6.1 mmol/l 3.5–5.5 mmol/l
Given these results, which is the most likely cause of his symptoms? -
This question is part of the following fields:
- Pharmacology
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Question 24
Incorrect
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What is the mechanism of action of ezetimibe in the management of hyperlipidaemia?
Your Answer: Reduced expression of LDL receptors in the liver surface
Correct Answer: Prevent cholesterol absorption from the intestine
Explanation:Ezetimibe and its Mechanism of Action
Ezetimibe is a medication that works by reducing the absorption of cholesterol in the gut. Although the exact way it works is not fully understood, it is believed to decrease the activity of proteins in the brush border of enterocytes, which in turn reduces the absorption of lipids. Unlike other medications that bind to bile acids, ezetimibe is absorbed into the bloodstream.
This medication is particularly useful for patients who cannot tolerate statins, those who are not achieving their cholesterol targets with statins alone, or those who have experienced serious side effects from statin use. When taken alone at a dose of 10 mg per day, ezetimibe can reduce LDL cholesterol levels by approximately 20%. However, increasing the dosage beyond this point does not typically improve its effectiveness.
When used in combination with statins, ezetimibe can lead to even greater reductions in LDL cholesterol levels. Overall, ezetimibe is a valuable medication for managing high cholesterol levels in patients who are unable to take or benefit from statins alone.
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This question is part of the following fields:
- Pharmacology
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Question 25
Incorrect
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A 25-year-old man presents to the emergency department 2 hours after ingesting approximately 70 of his mother's blood pressure pills following a recent breakup. He reports feeling fatigued, experiencing heart palpitations, and noticing a yellow-green tint to his vision. The medical team conducts observations, an ECG, and urgent blood tests. The ECG reveals sinus tachycardia. Oxygen saturation on air is 98%, heart rate is 115, blood pressure is 130/85 mmHg, and respiratory rate is 16. The blood tests show hyperkalemia with a potassium level of 6.5 mmol/L (3.5 - 5.0). The appropriate definitive management, besides treating the hyperkalemia, is what?
Your Answer: Admit to ICU for monitoring
Correct Answer: Administer Digibind
Explanation:The recommended initial treatment for severe digoxin toxicity is Digibind. The patient’s symptoms, such as a yellow-green tinge to vision and lethargy, strongly suggest a digoxin overdose. Administering 50g activated charcoal within an hour of ingestion may be helpful, but it is no longer applicable in this case. Watchful waiting is not advisable due to the severity of the overdose. Although the patient’s vital signs are currently normal except for tachycardia, admission to a coronary care unit (CCU) is necessary. While EDTA is a chelating agent used for heavy metal poisoning, it is not relevant to this case.
Understanding Digoxin and Its Toxicity
Digoxin is a medication used for rate control in atrial fibrillation and for improving symptoms in heart failure patients. It works by decreasing conduction through the atrioventricular node and increasing the force of cardiac muscle contraction. However, it has a narrow therapeutic index and requires monitoring for toxicity.
Toxicity may occur even when the digoxin concentration is within the therapeutic range. Symptoms of toxicity include lethargy, nausea, vomiting, anorexia, confusion, yellow-green vision, arrhythmias, and gynaecomastia. Hypokalaemia is a classic precipitating factor, as it allows digoxin to more easily bind to the ATPase pump and increase its inhibitory effects. Other factors that may contribute to toxicity include increasing age, renal failure, myocardial ischaemia, electrolyte imbalances, hypoalbuminaemia, hypothermia, hypothyroidism, and certain medications such as amiodarone, quinidine, and verapamil.
Management of digoxin toxicity involves the use of Digibind, correction of arrhythmias, and monitoring of potassium levels. It is important to recognize the potential for toxicity and monitor patients accordingly to prevent adverse outcomes.
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This question is part of the following fields:
- Pharmacology
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Question 26
Correct
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A 43-year-old man arrives at the emergency department after experiencing a convulsive episode while heavily drinking at a friend's party. Despite having no history of seizures, he has a medical background of depression and is currently taking sertraline. Urine toxicology reveals a significant amount of cocaine and small traces of cannabis. What is the probable reason for his seizure?
Your Answer: Cocaine toxicity
Explanation:Seizures are a known symptom of cocaine toxicity, making it the most probable cause in this case. While cannabis was detected in the patient’s system, the low level makes it an unlikely culprit compared to cocaine. Alcohol withdrawal can also lead to seizures, but this is more common in chronic alcoholics and unlikely in this patient who has just stopped drinking. While it is possible that this is the patient’s first epileptic seizure, it is more likely that cocaine is the cause. Additionally, there is no indication of hyponatremia in the patient’s history.
Understanding Cocaine Toxicity
Cocaine is a popular recreational stimulant derived from the coca plant. However, its widespread use has resulted in an increase in cocaine toxicity cases. The drug works by blocking the uptake of dopamine, noradrenaline, and serotonin, leading to a variety of adverse effects.
Cardiovascular effects of cocaine include coronary artery spasm, tachycardia, bradycardia, hypertension, QRS widening, QT prolongation, and aortic dissection. Neurological effects may include seizures, mydriasis, hypertonia, and hyperreflexia. Psychiatric effects such as agitation, psychosis, and hallucinations may also occur. Other complications include ischaemic colitis, hyperthermia, metabolic acidosis, and rhabdomyolysis.
Managing cocaine toxicity involves using benzodiazepines as a first-line treatment for most cocaine-related problems. For chest pain, benzodiazepines and glyceryl trinitrate may be used, and primary percutaneous coronary intervention may be necessary if myocardial infarction develops. Hypertension can be treated with benzodiazepines and sodium nitroprusside. The use of beta-blockers in cocaine-induced cardiovascular problems is controversial, with some experts warning against it due to the risk of unopposed alpha-mediated coronary vasospasm.
In summary, cocaine toxicity can lead to a range of adverse effects, and managing it requires careful consideration of the patient’s symptoms and medical history.
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This question is part of the following fields:
- Pharmacology
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Question 27
Incorrect
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What is a true statement about gentamicin treatment?
Your Answer: Is associated with axonal peripheral neuropathy
Correct Answer: May produce ventilatory failure in sensitive patients
Explanation:Aminoglycosides and Their Side Effects
Aminoglycosides are a class of antibiotics that can cause oto and renal toxicity, which is why drug concentrations need to be closely monitored during treatment. These antibiotics are primarily excreted by the kidneys, so any impairment in renal function can lead to increased toxicity. Additionally, a rare side effect of aminoglycosides is ventilatory failure, which is associated with impaired neuromuscular junction conduction. Therefore, patients with myasthenia gravis should not be given aminoglycosides.
Aminoglycosides are administered intravenously and cannot be taken orally because they are denatured in the digestive system. It is important to note that these antibiotics are reserved for serious infections due to their potential for toxicity. Patients receiving aminoglycosides should be closely monitored for any signs of toxicity, including hearing loss, kidney damage, and neuromuscular weakness. Overall, aminoglycosides are effective antibiotics, but their use should be carefully considered and monitored to minimize the risk of adverse effects.
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This question is part of the following fields:
- Pharmacology
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Question 28
Incorrect
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A 25-year-old woman with epilepsy visits the well woman clinic complaining of weight gain, acne, and hair loss. Her thyroid function is within normal limits. She is concerned that her epilepsy medication may be the culprit. Which of the following medications is the most probable cause?
Your Answer: Carbamazepine
Correct Answer: Valproate
Explanation:Sodium Valproate and PCOS-Like Syndrome
Sodium valproate is a medication that can cause a PCOS-like syndrome in some women who take it. This syndrome is characterized by weight gain, acne, and hirsutism. However, these symptoms gradually resolve once the medication is discontinued. For young female patients with epilepsy, lamotrigine is often the first choice agent as it does not cause a PCOS-like syndrome. Unlike carbamazepine or phenytoin, lamotrigine is not an enzyme inducer, which means it does not interfere with the effectiveness of oral contraceptives.
Topiramate, on the other hand, has been studied as a potential weight loss agent. While it is not associated with a PCOS-like syndrome, it is important to note that all medications have potential side effects and should be discussed with a healthcare provider before use. Overall, it is important for women to be aware of the potential effects of medications on their reproductive and metabolic health.
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This question is part of the following fields:
- Pharmacology
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Question 29
Incorrect
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A 26-year-old graduate student presents to the emergency department with a headache that has been ongoing for 8 hours. He reports feeling nauseous and has vomited once. The headache developed gradually over an hour, and he has been in bed with the curtains drawn all day. His housemates are all well. He has a history of smoking one pack of cigarettes a day and drinking 6-7 mugs of instant coffee. On examination, he has photophobia and is unable to tolerate a full cranial nerve examination. There is no nuchal rigidity. His vital signs are within normal limits, and his arterial blood gas shows a pH of 7.39, PaO2 of 11 kPa, PaCO2 of 5.6 kPa, cHCO3 of 23 mmol/L, and COHb of 8%. What is the most likely cause of his symptoms?
Your Answer: Carbon monoxide poisoning
Correct Answer: Migraine
Explanation:A smoker typically has a normal COHb level, whereas in cases of carbon monoxide poisoning, the COHb level is expected to be at least 10 or higher.
Understanding Carbon Monoxide Poisoning
Carbon monoxide poisoning occurs when carbon monoxide, a toxic gas, is inhaled and binds to haemoglobin and myoglobin in the body, resulting in tissue hypoxia. This leads to a left-shift of the oxygen dissociation curve, causing a decrease in oxygen saturation of haemoglobin. In the UK, there are approximately 50 deaths per year from accidental carbon monoxide poisoning.
Symptoms of carbon monoxide toxicity include headache, nausea and vomiting, vertigo, confusion, and subjective weakness. Severe toxicity can result in pink skin and mucosae, hyperpyrexia, arrhythmias, extrapyramidal features, coma, and even death.
To diagnose carbon monoxide poisoning, pulse oximetry may not be reliable due to similarities between oxyhaemoglobin and carboxyhaemoglobin. Therefore, a venous or arterial blood gas should be taken to measure carboxyhaemoglobin levels. Non-smokers typically have levels below 3%, while smokers have levels below 10%. Symptomatic patients have levels between 10-30%, and severe toxicity is indicated by levels above 30%. An ECG may also be useful to check for cardiac ischaemia.
In the emergency department, patients with suspected carbon monoxide poisoning should receive 100% high-flow oxygen via a non-rebreather mask. This decreases the half-life of carboxyhemoglobin and should be administered as soon as possible, with treatment continuing for a minimum of six hours. Target oxygen saturations are 100%, and treatment is generally continued until all symptoms have resolved. For more severe cases, hyperbaric oxygen therapy may be considered, as it has been shown to have better long-term outcomes than standard oxygen therapy. Indications for hyperbaric oxygen therapy include loss of consciousness, neurological signs other than headache, myocardial ischaemia or arrhythmia, and pregnancy.
Overall, understanding the pathophysiology, symptoms, and management of carbon monoxide poisoning is crucial in preventing and treating this potentially deadly condition.
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This question is part of the following fields:
- Pharmacology
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Question 30
Incorrect
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Which one of the following statements regarding the reporting of medication related adverse events using the Yellow Card scheme is accurate?
Your Answer: A persistent cough secondary to ramipril should be reported
Correct Answer: Diarrhoea occuring after starting a black triangle medicine should be reported
Explanation:The Yellow Card Scheme for Reporting Adverse Reactions to Medications
The Yellow Card scheme is a widely recognized method for reporting adverse reactions to medications. It is managed by the Medicines and Healthcare products Regulatory Agency (MHRA). The scheme is designed to encourage healthcare professionals and patients to report any suspected adverse drug reactions, including those related to new medicines, off-label use of medicines, and herbal remedies.
The MHRA recommends that all suspected adverse drug reactions for new medicines, identified by the black triangle symbol, should be reported. Additionally, all suspected adverse drug reactions occurring in children, even if a medicine has been used off-label, should be reported. Serious suspected adverse drug reactions for established vaccines and medicines, including unlicensed medicines, should also be reported.
Yellow Cards can be found at the back of the British National Formulary (BNF) or completed online through the Yellow Card website. It is important to note that any suspected reactions, not just confirmed ones, should be reported. Patients can also report adverse events through the scheme.
Once Yellow Cards are submitted, the MHRA collates and assesses the information. The agency may consult with the Commission on Human Medicines (CHM), an independent scientific advisory body on medicines safety, to further evaluate the reported adverse reactions. Reactions that are fatal, life-threatening, disabling or incapacitating, result in or prolong hospitalization, or are medically significant are considered serious.
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This question is part of the following fields:
- Pharmacology
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