The primary treatment for malignant hyperthermia is dantrolene. Dantrolene works by blocking the release of calcium through calcium channels, resulting in the relaxation of skeletal muscles.

Further Reading:

Malignant hyperthermia is a rare and life-threatening syndrome that can be triggered by certain medications in individuals who are genetically susceptible. The most common triggers are suxamethonium and inhalational anaesthetic agents. The syndrome is caused by the release of stored calcium ions from skeletal muscle cells, leading to uncontrolled muscle contraction and excessive heat production. This results in symptoms such as high fever, sweating, flushed skin, rapid heartbeat, and muscle rigidity. It can also lead to complications such as acute kidney injury, rhabdomyolysis, and metabolic acidosis. Treatment involves discontinuing the trigger medication, administering dantrolene to inhibit calcium release and promote muscle relaxation, and managing any associated complications such as hyperkalemia and acidosis. Referral to a malignant hyperthermia center for further investigation is also recommended.

Gynaecomastia, a condition characterized by the enlargement of breast tissue in males, can be caused by certain drugs. Some medications that have been associated with gynaecomastia include Cimetidine, Omeprazole, Spironolactone, Digoxin, Furosemide, Finasteride, and certain antipsychotics. Interestingly, Ranitidine, another medication commonly used for gastric issues, does not tend to cause gynaecomastia. In fact, studies have shown that gynaecomastia caused by Cimetidine can be resolved when it is substituted with Ranitidine.

Patients who have taken an overdose of tricyclic antidepressants (TCAs) should not be given phenytoin.

Further Reading:

Tricyclic antidepressant (TCA) overdose is a common occurrence in emergency departments, with drugs like amitriptyline and dosulepin being particularly dangerous. TCAs work by inhibiting the reuptake of norepinephrine and serotonin in the central nervous system. In cases of toxicity, TCAs block various receptors, including alpha-adrenergic, histaminic, muscarinic, and serotonin receptors. This can lead to symptoms such as hypotension, altered mental state, signs of anticholinergic toxicity, and serotonin receptor effects.

TCAs primarily cause cardiac toxicity by blocking sodium and potassium channels. This can result in a slowing of the action potential, prolongation of the QRS complex, and bradycardia. However, the blockade of muscarinic receptors also leads to tachycardia in TCA overdose. QT prolongation and Torsades de Pointes can occur due to potassium channel blockade. TCAs can also have a toxic effect on the myocardium, causing decreased cardiac contractility and hypotension.

Early symptoms of TCA overdose are related to their anticholinergic properties and may include dry mouth, pyrexia, dilated pupils, agitation, sinus tachycardia, blurred vision, flushed skin, tremor, and confusion. Severe poisoning can lead to arrhythmias, seizures, metabolic acidosis, and coma. ECG changes commonly seen in TCA overdose include sinus tachycardia, widening of the QRS complex, prolongation of the QT interval, and an R/S ratio >0.7 in lead aVR.

Management of TCA overdose involves ensuring a patent airway, administering activated charcoal if ingestion occurred within 1 hour and the airway is intact, and considering gastric lavage for life-threatening cases within 1 hour of ingestion. Serial ECGs and blood gas analysis are important for monitoring. Intravenous fluids and correction of hypoxia are the first-line therapies. IV sodium bicarbonate is used to treat haemodynamic instability caused by TCA overdose, and benzodiazepines are the treatment of choice for seizure control. Other treatments that may be considered include glucagon, magnesium sulfate, and intravenous lipid emulsion.

There are certain things to avoid in TCA overdose, such as anti-arrhythmics like quinidine and flecainide, as they can prolonged depolarization.

Flumazenil is a specific antagonist for benzodiazepines that can be beneficial in certain situations. It acts quickly, taking less than 1 minute to take effect, but its effects are short-lived and only last for less than 1 hour. The recommended dosage is 200 μg every 1-2 minutes, with a maximum dose of 3mg per hour.

It is important to avoid using Flumazenil if the patient is dependent on benzodiazepines or is taking tricyclic antidepressants. This is because it can trigger a withdrawal syndrome in these individuals, potentially leading to seizures or cardiac arrest.

During the third trimester of pregnancy, the use of selective serotonin reuptake inhibitors (SSRIs) has been associated with a discontinuation syndrome and persistent pulmonary hypertension of the newborn. It is important to be aware of the adverse effects of various drugs during pregnancy. For example, ACE inhibitors like ramipril, if given in the second and third trimester, can cause hypoperfusion, renal failure, and the oligohydramnios sequence. Aminoglycosides such as gentamicin can lead to ototoxicity and deafness. High doses of aspirin can result in first-trimester abortions, delayed onset labor, premature closure of the fetal ductus arteriosus, and fetal kernicterus. However, low doses (e.g., 75 mg) do not pose significant risks. Late administration of benzodiazepines like diazepam during pregnancy can cause respiratory depression and a neonatal withdrawal syndrome. Calcium-channel blockers, if given in the first trimester, may cause phalangeal abnormalities, while their use in the second and third trimester can lead to fetal growth retardation. Carbamazepine has been associated with hemorrhagic disease of the newborn and neural tube defects. Chloramphenicol can cause grey baby syndrome. Corticosteroids, if given in the first trimester, may cause orofacial clefts. Danazol, if administered in the first trimester, can result in masculinization of the female fetuses genitals. Pregnant women should avoid handling crushed or broken tablets of finasteride as it can be absorbed through the skin and affect male sex organ development. Haloperidol, if given in the first trimester, may cause limb malformations, while its use in the third trimester increases the risk of extrapyramidal symptoms in the neonate. Heparin can lead to maternal bleeding and thrombocytopenia. Isoniazid can cause maternal liver damage and neuropathy and seizures in the neonate. Isotretinoin carries a high risk of teratogenicity, including multiple congenital malformations, spontaneous abortion, and intellectual disability. The use of lithium in the first trimester increases the risk of fetal cardiac malformations, while its use in the second and third trimesters can result in hypotonia, lethargy, feeding problems, hypothyroidism, goiter, and nephrogenic diabetes insipidus.

Activated charcoal should be given to patients who have ingested paracetamol and meet two criteria: they must present within one hour of ingestion, and they must have taken a dose of paracetamol that is equal to or greater than 150 mg/kg. The recommended dose of activated charcoal is 50g, which is typically administered as 300ml. It is important to note that the dose criteria of 150 mg/kg is based on the amount of paracetamol reported by the patient, not on paracetamol levels, which should not be assessed until at least four hours after ingestion.

Further Reading:

Paracetamol poisoning occurs when the liver is unable to metabolize paracetamol properly, leading to the production of a toxic metabolite called N-acetyl-p-benzoquinone imine (NAPQI). Normally, NAPQI is conjugated by glutathione into a non-toxic form. However, during an overdose, the liver’s conjugation systems become overwhelmed, resulting in increased production of NAPQI and depletion of glutathione stores. This leads to the formation of covalent bonds between NAPQI and cell proteins, causing cell death in the liver and kidneys.

Symptoms of paracetamol poisoning may not appear for the first 24 hours or may include abdominal symptoms such as nausea and vomiting. After 24 hours, hepatic necrosis may develop, leading to elevated liver enzymes, right upper quadrant pain, and jaundice. Other complications can include encephalopathy, oliguria, hypoglycemia, renal failure, and lactic acidosis.

The management of paracetamol overdose depends on the timing and amount of ingestion. Activated charcoal may be given if the patient presents within 1 hour of ingesting a significant amount of paracetamol. N-acetylcysteine (NAC) is used to increase hepatic glutathione production and is given to patients who meet specific criteria. Blood tests are taken to assess paracetamol levels, liver function, and other parameters. Referral to a medical or liver unit may be necessary, and psychiatric follow-up should be considered for deliberate overdoses.

In cases of staggered ingestion, all patients should be treated with NAC without delay. Blood tests are also taken, and if certain criteria are met, NAC can be discontinued. Adverse reactions to NAC are common and may include anaphylactoid reactions, rash, hypotension, and nausea. Treatment for adverse reactions involves medications such as chlorpheniramine and salbutamol, and the infusion may be stopped if necessary.

The prognosis for paracetamol poisoning can be poor, especially in cases of severe liver injury. Fulminant liver failure may occur, and liver transplant may be necessary. Poor prognostic indicators include low arterial pH, prolonged prothrombin time, high plasma creatinine, and hepatic encephalopathy.

The clinical manifestations of theophylline toxicity are more closely associated with acute poisoning rather than chronic overexposure. The primary clinical features of theophylline toxicity include headache, dizziness, nausea and vomiting, abdominal pain, tachycardia and dysrhythmias, seizures, mild metabolic acidosis, hypokalaemia, hypomagnesaemia, hypophosphataemia, hypo- or hypercalcaemia, and hyperglycaemia. Seizures are more prevalent in cases of acute overdose compared to chronic overexposure. In contrast, chronic theophylline overdose typically presents with minimal gastrointestinal symptoms. Cardiac dysrhythmias are more frequently observed in individuals who have experienced chronic overdose rather than acute overdose.

Amiodarone is a medication that can have numerous harmful side effects, making it crucial to conduct a comprehensive clinical assessment before starting treatment with it. Some of the side effects associated with amiodarone include corneal microdeposits, photosensitivity, nausea, sleep disturbance, hyperthyroidism, hypothyroidism, acute hepatitis and jaundice, peripheral neuropathy, lung fibrosis, QT prolongation, and optic neuritis (although this is very rare). If optic neuritis occurs, immediate discontinuation of amiodarone is necessary to prevent the risk of blindness.

The majority of patients taking amiodarone experience corneal microdeposits, but these typically resolve after treatment is stopped and rarely affect vision. Amiodarone has a chemical structure similar to thyroxine and can bind to the nuclear thyroid receptor, leading to both hypothyroidism and hyperthyroidism. However, hypothyroidism is more commonly observed, affecting around 5-10% of patients.

The use of NSAIDs in the third trimester of pregnancy is linked to several risks. These risks include delayed onset of labor, premature closure of the fetal ductus arteriosus, and fetal kernicterus, which is a condition where bilirubin causes brain dysfunction. Additionally, there is a slight increase in the risk of first-trimester abortion if NSAIDs are used early in pregnancy.

Below is a list outlining commonly encountered drugs that have adverse effects during pregnancy:

ACE inhibitors (e.g. ramipril): If given in the second and third trimester, these drugs can cause hypoperfusion, renal failure, and the oligohydramnios sequence.

Aminoglycosides (e.g. gentamicin): These drugs can cause ototoxicity and deafness.

Aspirin: High doses of aspirin can lead to first-trimester abortions, delayed onset of labor, premature closure of the fetal ductus arteriosus, and fetal kernicterus. However, low doses (e.g. 75 mg) do not pose a significant risk.

Benzodiazepines (e.g. diazepam): When given late in pregnancy, these drugs can cause respiratory depression and a neonatal withdrawal syndrome.

Calcium-channel blockers: If given in the first trimester, these drugs can cause phalangeal abnormalities. If given in the second and third trimester, they can lead to fetal growth retardation.

Carbamazepine: This drug can cause hemorrhagic disease of the newborn and neural tube defects.

Chloramphenicol: Use of this drug can result in grey baby syndrome.

Corticosteroids: If given in the first trimester, corticosteroids may cause orofacial clefts.

Danazol: If given in the first trimester, this drug can cause masculinization of the female fetuses genitals.

Finasteride: Pregnant women should avoid handling finasteride. Crushed or broken tablets can be absorbed through the skin and affect male sex organ development.

Haloperidol: If given in the first trimester, this drug may cause limb malformations. If given in the third trimester, there is an increased risk of extrapyramidal symptoms in the neonate.

Heparin: Use of heparin during pregnancy can lead to maternal bleeding and thrombocytopenia.

Isoniazid: This drug can cause maternal liver damage

The most suitable dosage of epinephrine for a patient experiencing anaphylaxis after a flu vaccination is 500 micrograms (0.5ml 1 in 1,000) adrenaline by intramuscular injection.

Anaphylaxis is a severe and life-threatening hypersensitivity reaction that can have sudden onset and progression. It is characterized by skin or mucosal changes and can lead to life-threatening airway, breathing, or circulatory problems. Anaphylaxis can be allergic or non-allergic in nature.

In allergic anaphylaxis, there is an immediate hypersensitivity reaction where an antigen stimulates the production of IgE antibodies. These antibodies bind to mast cells and basophils. Upon re-exposure to the antigen, the IgE-covered cells release histamine and other inflammatory mediators, causing smooth muscle contraction and vasodilation.

Non-allergic anaphylaxis occurs when mast cells degrade due to a non-immune mediator. The clinical outcome is the same as in allergic anaphylaxis.

The management of anaphylaxis is the same regardless of the cause. Adrenaline is the most important drug and should be administered as soon as possible. The recommended doses for adrenaline vary based on age. Other treatments include high flow oxygen and an IV fluid challenge. Corticosteroids and chlorpheniramine are no longer recommended, while non-sedating antihistamines may be considered as third-line treatment after initial stabilization of airway, breathing, and circulation.

Common causes of anaphylaxis include food (such as nuts, which is the most common cause in children), drugs, and venom (such as wasp stings). Sometimes it can be challenging to determine if a patient had a true episode of anaphylaxis. In such cases, serum tryptase levels may be measured, as they remain elevated for up to 12 hours following an acute episode of anaphylaxis.

The Resuscitation Council (UK) provides guidelines for the management of anaphylaxis, including a visual algorithm that outlines the recommended steps for treatment.
https://www.resus.org.uk/sites/default/files/2021-05/Emergency%20Treatment%20of%20Anaphylaxis%20May%202021_0.pdf

During the first trimester of pregnancy, the use of warfarin can lead to a condition known as fetal warfarin syndrome. This condition is characterized by nasal hypoplasia, bone stippling, bilateral optic atrophy, and intellectual disability in the baby. However, if warfarin is taken during the second or third trimester, it can cause optic atrophy, cataracts, microcephaly, microphthalmia, intellectual disability, and both fetal and maternal hemorrhage.

There are several other drugs that can have adverse effects during pregnancy. For example, ACE inhibitors like ramipril can cause hypoperfusion, renal failure, and the oligohydramnios sequence if taken during the second and third trimesters. Aminoglycosides such as gentamicin can lead to ototoxicity and deafness in the baby. High doses of aspirin can result in first trimester abortions, delayed onset labor, premature closure of the fetal ductus arteriosus, and fetal kernicterus. However, low doses of aspirin (e.g. 75 mg) do not pose significant risks.

Benzodiazepines like diazepam, when taken late in pregnancy, can cause respiratory depression and a neonatal withdrawal syndrome. Calcium-channel blockers, if taken during the first trimester, can cause phalangeal abnormalities, while their use in the second and third trimesters can lead to fetal growth retardation. Carbamazepine can result in hemorrhagic disease of the newborn and neural tube defects. Chloramphenicol can cause gray baby syndrome. Corticosteroids, if taken during the first trimester, may cause orofacial clefts.

Danazol, if taken during the first trimester, can cause masculinization of the female fetuses genitals. Finasteride should not be handled by pregnant women as crushed or broken tablets can be absorbed through the skin and affect male sex organ development. Haloperidol, if taken during the first trimester, may cause limb malformations, while its use in the third trimester increases the risk of extrapyramidal symptoms in the newborn.

Heparin can lead to maternal bleeding and thrombocytopenia. Isoniazid can cause maternal liver damage and neuropathy and seizures in the baby. Isotretinoin carries a high risk of teratogenicity, including multiple congenital malformations and spontaneous abortion.

In order to achieve satisfactory bronchodilation, most individuals require a plasma theophylline concentration of 10-20 mg/litre (55-110 micromol/litre). However, it is possible for a lower concentration to still be effective. Adverse effects can occur within the range of 10-20 mg/litre, and their frequency and severity increase when concentrations exceed 20 mg/litre.

To measure plasma theophylline concentration, a blood sample should be taken five days after starting oral treatment and at least three days after any dose adjustment. For modified-release preparations, the blood sample should typically be taken 4-6 hours after an oral dose (specific sampling times may vary, so it is advisable to consult local guidelines). If aminophylline is administered intravenously, a blood sample should be taken 4-6 hours after initiating treatment.

When someone takes too much paracetamol, it can harm their liver cells and the tubules in their kidneys. This is because paracetamol produces a harmful substance called NAPQI, which is normally combined with glutathione. However, when there is too much NAPQI, it can cause damage and death to liver and kidney cells.

Further Reading:

Paracetamol poisoning occurs when the liver is unable to metabolize paracetamol properly, leading to the production of a toxic metabolite called N-acetyl-p-benzoquinone imine (NAPQI). Normally, NAPQI is conjugated by glutathione into a non-toxic form. However, during an overdose, the liver’s conjugation systems become overwhelmed, resulting in increased production of NAPQI and depletion of glutathione stores. This leads to the formation of covalent bonds between NAPQI and cell proteins, causing cell death in the liver and kidneys.

Symptoms of paracetamol poisoning may not appear for the first 24 hours or may include abdominal symptoms such as nausea and vomiting. After 24 hours, hepatic necrosis may develop, leading to elevated liver enzymes, right upper quadrant pain, and jaundice. Other complications can include encephalopathy, oliguria, hypoglycemia, renal failure, and lactic acidosis.

The management of paracetamol overdose depends on the timing and amount of ingestion. Activated charcoal may be given if the patient presents within 1 hour of ingesting a significant amount of paracetamol. N-acetylcysteine (NAC) is used to increase hepatic glutathione production and is given to patients who meet specific criteria. Blood tests are taken to assess paracetamol levels, liver function, and other parameters. Referral to a medical or liver unit may be necessary, and psychiatric follow-up should be considered for deliberate overdoses.

In cases of staggered ingestion, all patients should be treated with NAC without delay. Blood tests are also taken, and if certain criteria are met, NAC can be discontinued. Adverse reactions to NAC are common and may include anaphylactoid reactions, rash, hypotension, and nausea. Treatment for adverse reactions involves medications such as chlorpheniramine and salbutamol, and the infusion may be stopped if necessary.

The prognosis for paracetamol poisoning can be poor, especially in cases of severe liver injury. Fulminant liver failure may occur, and liver transplant may be necessary. Poor prognostic indicators include low arterial pH, prolonged prothrombin time, high plasma creatinine, and hepatic encephalopathy.

Theophylline is a medication used to treat severe asthma. It is a bronchodilator that comes in modified-release forms, which can maintain therapeutic levels in the blood for 12 hours. Theophylline works by inhibiting phosphodiesterase and blocking the breakdown of cyclic AMP. It also competes with adenosine on A1 and A2 receptors.

Achieving the right dose of theophylline can be challenging because there is a narrow range between therapeutic and toxic levels. The half-life of theophylline can be influenced by various factors, further complicating dosage adjustments. It is recommended to aim for serum levels of 10-20 mg/l six to eight hours after the last dose.

Unlike many other medications, the specific brand of theophylline can significantly impact its effects. Therefore, it is important to prescribe theophylline by both its brand name and generic name.

Several factors can increase the half-life of theophylline, including heart failure, cirrhosis, viral infections, and certain drugs. Conversely, smoking, heavy drinking, and certain medications can decrease the half-life of theophylline.

There are several drugs that can either increase or decrease the plasma concentration of theophylline. Calcium channel blockers, cimetidine, fluconazole, macrolides, methotrexate, and quinolones can increase the concentration. On the other hand, carbamazepine, phenobarbitol, phenytoin, rifampicin, and St. John’s wort can decrease the concentration.

The clinical symptoms of theophylline toxicity are more closely associated with acute overdose rather than chronic overexposure. Common symptoms include headache, dizziness, nausea, vomiting, abdominal pain, rapid heartbeat, dysrhythmias, seizures, mild metabolic acidosis, low potassium, low magnesium, low phosphates, abnormal calcium levels, and high blood sugar.

Seizures are more prevalent in acute overdose cases, while chronic overdose typically presents with minimal gastrointestinal symptoms. Cardiac dysrhythmias are more common in chronic overdose situations compared to acute overdose.

There is a significant link between methotrexate and the development of pulmonary fibrosis. While there have been instances of pulmonary fibrosis occurring as a result of infliximab, this particular side effect is more commonly associated with methotrexate use.

Methotrexate can also cause other side effects such as nausea and vomiting, abdominal pain, gastrointestinal bleeding, dizziness, stomatitis, hepatotoxicity, neutropenia, and pneumonitis.

In managing patients with carbon monoxide poisoning, the primary intervention is providing 100% oxygen. This is because carbon monoxide has a higher affinity for hemoglobin than oxygen, leading to decreased oxygen delivery to tissues. By administering 100% oxygen, the patient is able to displace carbon monoxide from hemoglobin and increase oxygen levels in the blood, which is crucial for the patient’s recovery.

Further Reading:

Carbon monoxide (CO) is a dangerous gas that is produced by the combustion of hydrocarbon fuels and can be found in certain chemicals. It is colorless and odorless, making it difficult to detect. In England and Wales, there are approximately 60 deaths each year due to accidental CO poisoning.

When inhaled, carbon monoxide binds to haemoglobin in the blood, forming carboxyhaemoglobin (COHb). It has a higher affinity for haemoglobin than oxygen, causing a left-shift in the oxygen dissociation curve and resulting in tissue hypoxia. This means that even though there may be a normal level of oxygen in the blood, it is less readily released to the tissues.

The clinical features of carbon monoxide toxicity can vary depending on the severity of the poisoning. Mild or chronic poisoning may present with symptoms such as headache, nausea, vomiting, vertigo, confusion, and weakness. More severe poisoning can lead to intoxication, personality changes, breathlessness, pink skin and mucosae, hyperpyrexia, arrhythmias, seizures, blurred vision or blindness, deafness, extrapyramidal features, coma, or even death.

To help diagnose domestic carbon monoxide poisoning, there are four key questions that can be asked using the COMA acronym. These questions include asking about co-habitees and co-occupants in the house, whether symptoms improve outside of the house, the maintenance of boilers and cooking appliances, and the presence of a functioning CO alarm.

Typical carboxyhaemoglobin levels can vary depending on whether the individual is a smoker or non-smoker. Non-smokers typically have levels below 3%, while smokers may have levels below 10%. Symptomatic individuals usually have levels between 10-30%, and severe toxicity is indicated by levels above 30%.

When managing carbon monoxide poisoning, the first step is to administer 100% oxygen. Hyperbaric oxygen therapy may be considered for individuals with a COHb concentration of over 20% and additional risk factors such as loss of consciousness, neurological signs, myocardial ischemia or arrhythmia, or pregnancy. Other management strategies may include fluid resuscitation, sodium bicarbonate for metabolic acidosis, and mannitol for cerebral edema.

Loop diuretics, like furosemide, commonly result in several electrolyte imbalances. These imbalances include hyponatremia, which is a decrease in sodium levels in the blood. Another common imbalance is hypokalemia, which refers to low levels of potassium. Additionally, loop diuretics can cause hypocalcemia, a condition characterized by low levels of calcium in the blood. Another electrolyte affected by loop diuretics is magnesium, as they can lead to hypomagnesemia, which is a deficiency of magnesium. Lastly, loop diuretics can cause hypochloremic alkalosis, which is a condition characterized by low levels of chloride in the blood and an increase in blood pH.

Extrapyramidal side effects are most commonly seen with the piperazine phenothiazines (fluphenazine, prochlorperazine, and trifluoperazine) and butyrophenones (benperidol and haloperidol). Among these, haloperidol is the most frequently implicated antipsychotic drug.

Tardive dyskinesia, which involves involuntary rhythmic movements of the tongue, face, and jaw, typically occurs after prolonged treatment or high doses. It is the most severe manifestation of extrapyramidal symptoms, as it may become irreversible even after discontinuing the causative medication, and treatment options are generally ineffective.

Dystonia, characterized by abnormal movements of the face and body, is more commonly observed in children and young adults and tends to appear after only a few doses. Acute dystonia can be managed with intravenous administration of procyclidine (5 mg) or benzatropine (2 mg) as a bolus.

Akathisia refers to an unpleasant sensation of restlessness, while akinesia refers to an inability to initiate movement.

In individuals with renal impairment, there is an increased sensitivity of the brain to antipsychotic drugs, necessitating the use of reduced doses.

Elderly patients with dementia-related psychosis who are treated with haloperidol face an elevated risk of mortality. This is believed to be due to an increased likelihood of cardiovascular events and infections such as pneumonia.

Contraindications for the use of antipsychotic drugs include reduced consciousness or coma, central nervous system depression, and the presence of phaeochromocytoma.

The earliest and most common clinical indication of malignant hyperthermia is typically an increase in end tidal CO2 levels.

Further Reading:

Malignant hyperthermia is a rare and life-threatening syndrome that can be triggered by certain medications in individuals who are genetically susceptible. The most common triggers are suxamethonium and inhalational anaesthetic agents. The syndrome is caused by the release of stored calcium ions from skeletal muscle cells, leading to uncontrolled muscle contraction and excessive heat production. This results in symptoms such as high fever, sweating, flushed skin, rapid heartbeat, and muscle rigidity. It can also lead to complications such as acute kidney injury, rhabdomyolysis, and metabolic acidosis. Treatment involves discontinuing the trigger medication, administering dantrolene to inhibit calcium release and promote muscle relaxation, and managing any associated complications such as hyperkalemia and acidosis. Referral to a malignant hyperthermia center for further investigation is also recommended.

Phenytoin is a potent anti-epileptic drug that is no longer recommended as the initial treatment for generalized or partial epilepsy due to its toxic effects. Users often experience common symptoms such as ataxia, nystagmus, diplopia, tremor, and dysarthria. Additionally, other side effects may include depression, decreased cognitive abilities, coarse facial features, acne, gum enlargement, polyneuropathy, and blood disorders.