This question is challenging as it requires an estimation of the percentage of Caucasians who possess two copies of the gene responsible for the slow-acting form of alcohol dehydrogenase.

Genetics and Alcoholism

Alcoholism tends to run in families, and several studies confirm that biological children of alcoholics are more likely to develop alcoholism even when adopted by parents without the condition. Monozygotic twins have a greater concordance rate for alcoholism than dizygotic twins. Heritability estimates range from 45 to 65 percent for both men and women. While genetic differences affect risk, there is no “gene for alcoholism,” and both environmental and social factors weigh heavily on the outcome.

The genes with the clearest contribution to the risk for alcoholism and alcohol consumption are alcohol dehydrogenase 1B (ADH1B) and aldehyde dehydrogenase 2 (ALDH2). The first step in ethanol metabolism is oxidation to acetaldehyde, by ADHs. The second step is metabolism of the acetaldehyde to acetate by ALDHs. Individuals carrying even a single copy of the ALDH2*504K display the “Asian flushing reaction” when they consume even small amounts of alcohol. There is one significant genetic polymorphism of the ALDH2 gene, resulting in allelic variants ALDH2*1 and ALDH2*2, which is virtually inactive. ALDH2*2 is present in about 50 percent of the Taiwanese, Han Chinese, and Japanese populations. It is extremely rare outside Asia. Nearly no individuals of European of African descent carry this allele. ALDH2*504K has repeatedly been demonstrated to have a protective effect against alcohol use disorders.

The three different class I gene loci, ADH1A (alpha), ADH1B (beta), and ADH1C (gamma) are situated close to each other in the region 4q2123. The alleles ADH1C*1 and ADH1B*2 code for fast metabolism of alcohol. The ADH1B*1 slow allele is very common among Caucasians, with approximately 95 percent having the homozygous ADH1B*1/1 genotype and 5 percent having the heterozygous ADH1B*1/2 genotype. The ADH1B*2 allele is the most common allele in Asian populations. In African populations, the ADH1B*1 allele is the most common.

Tau and Tauopathies

Tau proteins are essential for maintaining the stability of microtubules in neurons. Microtubules provide structural support to the cell and facilitate the transport of molecules within the cell. Tau proteins are predominantly found in the axons of neurons and are absent in dendrites. The gene that codes for tau protein is located on chromosome 17.

When tau proteins become hyperphosphorylated, they clump together, forming neurofibrillary tangles. This process leads to the disintegration of cells, which is a hallmark of several neurodegenerative disorders collectively known as tauopathies.

The major tauopathies include Alzheimer’s disease, Pick’s disease (frontotemporal dementia), progressive supranuclear palsy, and corticobasal degeneration. These disorders are characterized by the accumulation of tau protein in the brain, leading to the degeneration of neurons and cognitive decline. Understanding the role of tau proteins in these disorders is crucial for developing effective treatments for these devastating diseases.

Discontinuation symptoms are frequently observed in patients taking antidepressants with a shorter half-life, especially venlafaxine of paroxetine. These symptoms can be unsettling, and even patients who are aware of the cause may experience them for several days of longer if they do not resume taking the medication. Malignant hypertension is improbable since the blood pressure is not significantly elevated. Venlafaxine is not typically linked to neuroleptic malignant syndrome.

Edinburgh Postnatal Depression Scale (EPDS)

The Edinburgh Postnatal Depression Scale (EPDS) is a 10-item self-report questionnaire designed to screen for postnatal depression in primary care settings. It should only be used to assess a women’s mood over the past seven days and cannot be used to diagnose depression. The EPDS excludes some symptoms common in the perinatal period, such as tiredness and irritability, as they do not differentiate between depressed and non-depressed postnatal women. Women are asked to select one of four responses that most closely represents how they have felt over the past seven days. Scores for the 10 items are added together, with a score of 0-9 indicating a low likelihood of depression, 10-12 indicating a moderate likelihood, and 13 of more indicating a high likelihood. The statements include feelings of happiness, sadness, anxiety, and thoughts of self-harm.

Delusional Structure

Delusions can be categorized based on their logical consistency and organization. Logical delusions are consistent with logical thinking, while paralogical delusions are not. Delusions can also be organized, integrated into a formed concept, of unorganized. Highly organized, logical delusions are referred to as systematized.

The relationship between delusional beliefs and reality can also be described in different ways. Polarized delusions mix fact and delusion together, while juxtaposed delusions exist side by side with facts but do not interact. Autistic delusions completely disregard actual reality, and the patient lives in a delusional world.

XYY Syndrome

XYY Syndrome, also known as Jacobs’ Syndrome of super-males, is a genetic condition where males have an extra Y chromosome, resulting in a 47, XYY karyotype. In some cases, mosaicism may occur, resulting in a 47,XYY/46,XY karyotype. The error leading to the 47,XYY genotype occurs during spermatogenesis of post-zygotic mitosis. The prevalence of XYY Syndrome is as high as 1:1000 male live births, but many cases go unidentified as they are not necessarily associated with physical of cognitive impairments. The most common features are high stature and a strong build, and fertility and sexual development are usually unaffected. In the past, XYY Syndrome was linked to aggressiveness and deviance, but this is likely due to intermediate factors such as reduced IQ and social deprivation. XYY Syndrome is best thought of as a risk factor rather than a cause. There is an increased risk of developmental disorders such as learning difficulties, ASD, ADHD, and emotional problems.

Subtle impairments of motor or sensory function that are not specific to a particular neurological condition and are referred to as neurological ‘soft’ signs. These signs are prevalent in individuals with schizophrenia and may serve as a potential endophenotype.

Clozapine is an atypical antipsychotic drug that acts as an antagonist at various receptors, including dopamine, histamine, serotonin, adrenergic, and cholinergic receptors. It is mainly metabolized by CYP1A2, and its plasma levels can be affected by inducers and inhibitors of this enzyme. Clozapine is associated with several side effects, including drowsiness, constipation, weight gain, and hypersalivation. Hypersalivation is a paradoxical side effect, and its mechanism is not fully understood, but it may involve clozapine agonist activity at the muscarinic M4 receptor and antagonist activity at the alpha-2 adrenoceptor. Clozapine is also associated with several potentially dangerous adverse events, including agranulocytosis, myocarditis, seizures, severe orthostatic hypotension, increased mortality in elderly patients with dementia-related psychosis, colitis, pancreatitis, thrombocytopenia, thromboembolism, and insulin resistance and diabetes mellitus. The BNF advises caution in using clozapine in patients with prostatic hypertrophy, susceptibility to angle-closure glaucoma, and adults over 60 years. Valproate should be considered when using high doses of clozapine, plasma levels > 0.5 mg/l, of when the patient experiences seizures. Myocarditis is a rare but potentially fatal adverse event associated with clozapine use, and its diagnosis is based on biomarkers and clinical features. The mortality rate of clozapine-induced myocarditis is high, and subsequent use of clozapine in such cases leads to recurrence of myocarditis in most cases.

Anankastic personality disorder is a personality disorder characterized by a preoccupation with orderliness, perfectionism, and control. It falls under cluster C personality disorders according to DSM-IV classification.

Deliberate self-harm is commonly associated with cluster B personality disorders. In the United Kingdom, poisoning by drugs accounts for 90% of deliberate self-harm cases, while wrist cutting accounts for 6-7%, and all other methods combined account for 3-4%. Frequent wrist cutting can be a part of recurrent suicidal gestures seen in individuals with depressive disorder, schizophrenia, and borderline personality disorder.

The reasons for wrist cutting are varied and complex, including a means of punishment oneself, reducing tension, feeling bodily instead of emotional pain, wishing to die, testing the benevolence of fate, seeking an interruption to an unendurable state of tension, crying for help, communicating with others, and unbearable symptoms.

Borderline personality disorder (BPD) is characterized by impulsive acts, mood instability, and chaotic relationships. Individuals with BPD are impulsive in areas that have a potential for self-harm and exhibit recurrent suicidal gestures such as wrist cutting, overdose, of self-mutilation.

The foramen lacerum is a opening located in the middle cranial fossa at the base of the skull.

Cranial Fossae and Foramina

The cranium is divided into three regions known as fossae, each housing different cranial lobes. The anterior cranial fossa contains the frontal lobes and includes the frontal and ethmoid bones, as well as the lesser wing of the sphenoid. The middle cranial fossa contains the temporal lobes and includes the greater wing of the sphenoid, sella turcica, and most of the temporal bones. The posterior cranial fossa contains the occipital lobes, cerebellum, and medulla and includes the occipital bone.

There are several foramina in the skull that allow for the passage of various structures. The most important foramina likely to appear in exams are listed below:

– Foramen spinosum: located in the middle fossa and allows for the passage of the middle meningeal artery.
– Foramen ovale: located in the middle fossa and allows for the passage of the mandibular division of the trigeminal nerve.
– Foramen lacerum: located in the middle fossa and allows for the passage of the small meningeal branches of the ascending pharyngeal artery and emissary veins from the cavernous sinus.
– Foramen magnum: located in the posterior fossa and allows for the passage of the spinal cord.
– Jugular foramen: located in the posterior fossa and allows for the passage of cranial nerves IX, X, and XI.

Understanding the location and function of these foramina is essential for medical professionals, as they play a crucial role in the diagnosis and treatment of various neurological conditions.

ADHD medications can be classified into stimulant and non-stimulant drugs. The therapeutic effects of these drugs are believed to be mediated through the action of noradrenaline in the prefrontal cortex. Common side effects of these drugs include decreased appetite, insomnia, nervousness, headache, and nausea. Stimulant drugs like dexamphetamine, methylphenidate, and lisdexamfetamine inhibit the reuptake of dopamine and noradrenaline. Non-stimulant drugs like atomoxetine, guanfacine, and clonidine work by increasing noradrenaline levels in the synaptic cleft through different mechanisms. The most common side effects of these drugs are decreased appetite, somnolence, headache, and abdominal pain.

A pituitary adenoma can cause compression of the optic chiasm, resulting in a bitemporal hemianopia. Other tumors, such as craniopharyngiomas, meningiomas, of gliomas, can also cause this type of visual field defect. Cerebellopontine angle tumors typically present with symptoms related to the facial, vestibulocochlear, and trigeminal nerves. A cerebrovascular event in the occipital cortex can cause visual loss, usually in the form of a homonymous hemianopia. Diabetes mellitus can cause various visual defects, including diabetic retinopathy, retinal hemorrhages of detachment, and oculomotor nerve palsy. Oculomotor nerve palsies can be caused by a variety of conditions, such as vascular events, diabetic neuropathy, intracranial aneurysms, syphilis, of raised intracranial pressure. Symptoms include ptosis, diplopia, and possible mydriasis. Laser treatment for diabetic retinopathy is unlikely to cause a well-defined homonymous hemianopia.

– Lithium toxicity occurs at levels above 1.4 mmol/L
– Symptoms include anorexia, diarrhea, vomiting, ataxia, nystagmus, dysarthria, confusion, and seizures
– Fine tremor can occur in therapeutic range, but becomes coarser in toxicity
– If allowed to progress, toxicity can result in coma with hyperreflexia and increased tone, and irreversible neurological damage
– Treatment is supportive, with attention to electrolytes, fluid balance, renal function, and seizure control
– Bowel irrigation can be used in significant recent overdose, diuretics should be avoided, and haemodialysis may be required
– Benzodiazepines can control agitation.

While digit span is primarily used to assess working memory, it also involves executive attention, which is a component shared by tests of working memory capacity and executive function. Therefore, digit span cannot be considered solely a test of working memory.

The mental state exam assesses various areas of cognition, including orientation, attention/concentration, short term memory, long term memory, and executive function. Standard tests for each area include asking about time, place, and person for orientation, serial 7’s for attention/concentration, digit span for short term memory, delayed recall of name and address for long term memory, and various tasks such as proverbs, similarities, differences, verbal fluency, and cognitive estimates for executive function.

Huntington’s Disease: Genetics and Pathology

Huntington’s disease is a genetic disorder that follows an autosomal dominant pattern of inheritance. It is caused by a mutation in the Huntington gene, which is located on chromosome 4. The mutation involves an abnormal expansion of a trinucleotide repeat sequence (CAG), which leads to the production of a toxic protein that damages brain cells.

The severity of the disease and the age of onset are related to the number of CAG repeats. Normally, the CAG sequence is repeated less than 27 times, but in Huntington’s disease, it is repeated many more times. The disease shows anticipation, meaning that it tends to worsen with each successive generation.

The symptoms of Huntington’s disease typically begin in the third of fourth decade of life, but in rare cases, they can appear in childhood of adolescence. The most common symptoms include involuntary movements (chorea), cognitive decline, and psychiatric disturbances.

The pathological hallmark of Huntington’s disease is the gross bilateral atrophy of the head of the caudate and putamen, which are regions of the brain involved in movement control. The EEG of patients with Huntington’s disease shows a flattened trace, indicating a loss of brain activity.

Macroscopic pathological findings include frontal atrophy, marked atrophy of the caudate and putamen, and enlarged ventricles. Microscopic findings include neuronal loss and gliosis in the cortex, neuronal loss in the striatum, and the presence of inclusion bodies in the neurons of the cortex and striatum.

In conclusion, Huntington’s disease is a devastating genetic disorder that affects the brain and causes a range of motor, cognitive, and psychiatric symptoms. The disease is caused by a mutation in the Huntington gene, which leads to the production of a toxic protein that damages brain cells. The pathological changes in the brain include atrophy of the caudate and putamen, neuronal loss, and the presence of inclusion bodies.

Porphyria: The Little Imitator

Porphyria is a medical condition that is often referred to as the little imitator because it can mimic various common psychiatric presentations. This condition can be triggered by the use of certain psychotropic drugs, including barbiturates, benzodiazepines, sulpiride, and some mood stabilizers.

Porphyria can manifest in different ways, and it is important to be aware of the symptoms. These may include abdominal pain, mental state changes, constipation, vomiting, and muscle weakness.

Splicing of mRNA

After the transcription of DNA into mRNA, the mRNA undergoes a crucial process known as splicing. This process involves the removal of certain portions of the mRNA, called introns, leaving behind the remaining portions known as exons. The exons are then translated into proteins. The resulting spliced form of RNA is referred to as mature mRNA. This process of splicing is essential for the proper functioning of genes and the production of functional proteins.

Compared to other opioid receptors, methadone exhibits significantly greater affinity for mu receptors.

Opioid Pharmacology and Treatment Medications

Opioids work by binding to opioid receptors in the brain, specifically the µ, k, and δ receptors. The µ receptor is the main target for opioids and mediates euphoria, respiratory depression, and dependence. Dopaminergic cells in the ventral tegmental area produce dopamine, which is released into the nucleus accumbens upon stimulation of µ receptors, leading to the reward and euphoria that drives repeated use. However, with repeated exposure, µ receptors become less responsive, leading to dysphoria and drug craving.

There are several medications used in opioid treatment. Methadone is a full agonist targeting µ receptors, with some action against k and δ receptors, and has a half-life of 15-22 hours. However, it carries a risk of respiratory depression, especially when used with hypnotics and alcohol. Buprenorphine is a partial agonist targeting µ receptors, as well as a partial k agonist of functional antagonist and a weak δ antagonist. It has a high affinity for µ receptors and a longer half-life of 24-42 hours, making it safer than methadone. Naloxone is an antagonist targeting all opioid receptors and is used to reverse opioid overdose, with a half-life of 30-120 minutes. However, it can cause noncardiogenic pulmonary edema in some cases. Naltrexone is a reversible competitive antagonist at µ and ĸ receptors, with a half-life of 4-6 hours, and is used as an adjunctive prophylactic treatment for detoxified formerly opioid-dependent people.

Alpha2 adrenergic agonists, such as clonidine and lofexidine, can ameliorate opioid withdrawal symptoms associated with the noradrenaline system, including sweating, shivering, and runny nose and eyes. The locus coeruleus, a nucleus in the pons with a high density of noradrenergic neurons possessing µ-opioid receptors, is involved in wakefulness, blood pressure, breathing, and overall alertness. Exposure to opioids results in heightened neuronal activity of the nucleus cells, and if opioids are not present to suppress this activity, increased amounts of norepinephrine are released, leading to withdrawal symptoms. Clonidine was originally developed as an antihypertensive, but its antihypertensive effects are problematic in detox, so lofexidine was developed as an alternative with less hypotensive effects.

Cerebral Asymmetry in Planum Temporale and its Implications in Language and Auditory Processing

The planum temporale, a triangular region in the posterior superior temporal gyrus, is a highly lateralized brain structure involved in language and music processing. Studies have shown that the planum temporale is up to ten times larger in the left cerebral hemisphere than the right, with this asymmetry being more prominent in men. This asymmetry can be observed in gestation and is present in up to 70% of right-handed individuals.

Recent research suggests that the planum temporale also plays an important role in auditory processing, specifically in representing the location of sounds in space. However, reduced planum temporale asymmetry has been observed in individuals with dyslexia, stuttering, and schizophrenia. These findings highlight the importance of cerebral asymmetry in the planum temporale and its implications in language and auditory processing.

MAOIs: A Guide to Mechanism of Action, Adverse Effects, and Dietary Restrictions

First introduced in the 1950s, MAOIs were the first antidepressants introduced. However, they are not the first choice in treating mental health disorders due to several dietary restrictions and safety concerns. They are only a treatment option when all other medications are unsuccessful. MAOIs may be particularly useful in atypical depression (over eating / over sleeping, mood reactivity).

MAOIs block the monoamine oxidase enzyme, which breaks down different types of neurotransmitters from the brain: norepinephrine, serotonin, dopamine, as well as tyramine. There are two types of monoamine oxidase, A and B. The MOA A are mostly distributed in the placenta, gut, and liver, but MOA B is present in the brain, liver, and platelets. Selegiline and rasagiline are irreversible and selective inhibitors of MAO type B, but safinamide is a reversible and selective MAO B inhibitor.

The most common adverse effects of MAOIs occurring early in treatment are orthostatic hypotension, daytime sleepiness, insomnia, and nausea; later common effects include weight gain, muscle pain, myoclonus, paraesthesia, and sexual dysfunction.

Pharmacodynamic interactions with MAOIs can cause two types of problem: serotonin syndrome (mainly due to SSRIs) and elevated blood pressure (caused by indirectly acting sympathomimetic amines releasers, like pseudoephedrine and phenylephrine). The combination of MAOIs and some TCAs appears safe. Only those TCAs with significant serotonin reuptake inhibition (clomipramine and imipramine) are likely to increase the risk of serotonin syndrome.

Tyramine is a monoamine found in various foods, and is an indirect sympathomimetic that can cause a hypertensive reaction in patients receiving MAOI therapy. For this reason, dietary restrictions are required for patients receiving MAOIs. These restrictions include avoiding matured/aged cheese, fermented sausage, improperly stored meat, fava of broad bean pods, and certain drinks such as on-tap beer. Allowed foods include fresh cottage cheese, processed cheese slices, fresh packaged of processed meat, and other alcohol (no more than two bottled or canned beers of two standard glasses of wine, per day).

Agomelatine is a medication used to treat depression. It works by activating melatonin receptors (MT1 and MT2) and blocking serotonin 5-HT2C receptors.

Antidepressants can cause sexual dysfunction as a side-effect, although the rates vary. The impact on sexual desire, arousal, and orgasm can differ depending on the type of antidepressant. It is important to rule out other causes and consider non-pharmacological strategies such as reducing the dosage of taking drug holidays. If necessary, switching to a lower risk antidepressant of using pharmacological options such as phosphodiesterase inhibitors of mirtazapine augmentation can be considered. The Maudsley Guidelines 14th Edition provides a helpful table outlining the risk of sexual dysfunction for different antidepressants.

The cortex is composed of neurons, with the majority being pyramidal neurons that are excitatory and contain glutamate. Grey matter is where neural cell bodies are located, while white matter mainly consists of myelinated axon tracts. The color contrast between the two is due to the white appearance of myelin.

The Cerebral Cortex and Neocortex

The cerebral cortex is the outermost layer of the cerebral hemispheres and is composed of three parts: the archicortex, paleocortex, and neocortex. The neocortex accounts for 90% of the cortex and is involved in higher functions such as thought and language. It is divided into 6-7 layers, with two main cell types: pyramidal cells and nonpyramidal cells. The surface of the neocortex is divided into separate areas, each given a number by Brodmann (e.g. Brodmann’s area 17 is the primary visual cortex). The surface is folded to increase surface area, with grooves called sulci and ridges called gyri. The neocortex is responsible for higher cognitive functions and is essential for human consciousness.

Culture bound illnesses are psychiatric conditions that are specific to one particular culture. There are many different types of culture bound illnesses, including Amok, Shenjing shuairuo, Ataque de nervios, Bilis, colera, Bouffee delirante, Brain fag, Dhat, Falling-out, blacking out, Ghost sickness, Hwa-byung, wool-hwa-byung, Koro, Latah, Locura, Mal de ojo, Nervios, Rootwork, Pibloktoq, Qi-gong psychotic reaction, Sangue dormido, Shen-k’uei, shenkui, Shin-byung, Taijin kyofusho, Spell, Susto, Zar, and Wendigo.

Some of the most commonly discussed culture bound illnesses include Amok, which is confined to males in the Philippines and Malaysia who experience blind, murderous violence after a real of imagined insult. Ataque de nervios is a condition that occurs in those of Latino descent and is characterized by intense emotional upset, shouting uncontrollably, aggression, dissociation, seizure-like episodes, and suicidal gestures. Brain fag is a form of psychological distress first identified in Nigerian students in the 1960s but reported more generally in the African diaspora. It consists of a variety of cognitive and sensory disturbances that occur during periods of intense intellectual activity. Koro is a condition that affects Chinese patients who believe that their penis is withdrawing inside their abdomen, resulting in panic and the belief that they will die. Taijin kyofusho is a Japanese culture bound illness characterized by anxiety about and avoidance of interpersonal situations due to the thought, feeling, of conviction that one’s appearance and actions in social interactions are inadequate of offensive to others. Finally, Wendigo is a culture bound illness that occurs in Native American tribes during severe winters and scarcity of food, characterized by a distaste for food that leads to anxiety and the belief that one is turning into a cannibalistic ice spirit.

Common examples of acting out include avoiding therapy sessions and using alcohol as a means of avoiding the challenging work of therapy.

Intermediate Mechanism: Rationalisation

Rationalisation is a defense mechanism commonly used by individuals to create false but credible justifications for their behavior of actions. It involves the use of logical reasoning to explain away of justify unacceptable behavior of feelings. The individual may not be aware that they are using this mechanism, and it can be difficult to identify in oneself.

Rationalisation is considered an intermediate mechanism, as it is common in healthy individuals from ages three to ninety, as well as in neurotic disorders and in mastering acute adult stress. It can be dramatically changed by conventional psychotherapeutic interpretation.

Examples of rationalisation include a student who fails an exam and blames the teacher for not teaching the material well enough, of a person who cheats on their partner and justifies it by saying their partner was neglectful of unaffectionate. It allows the individual to avoid taking responsibility for their actions and to maintain a positive self-image.

Overall, rationalisation can be a useful defense mechanism in certain situations, but it can also be harmful if it leads to a lack of accountability and an inability to learn from mistakes.

Heritability: Understanding the Concept

Heritability is a concept that is often misunderstood. It is not a measure of the extent to which genes cause a condition in an individual. Rather, it is the proportion of phenotypic variance attributable to genetic variance. In other words, it tells us how much of the variation in a condition seen in a population is due to genetic factors. Heritability is calculated using statistical techniques and can range from 0.0 to 1.0. For human behavior, most estimates of heritability fall in the moderate range of .30 to .60.

The quantity (1.0 – heritability) gives the environment ability of the trait. This is the proportion of phenotypic variance attributable to environmental variance. The following table provides estimates of heritability for major conditions:

Condition Heritability estimate (approx)
ADHD 85%
Autism 70%
Schizophrenia 55%
Bipolar 55%
Anorexia 35%
Alcohol dependence 35%
Major depression 30%
OCD 25%

It is important to note that heritability tells us nothing about individuals. It is a population-level measure that helps us understand the relative contributions of genetic and environmental factors to a particular condition.

The half-life of a drug is the time taken for its concentration to fall to one half of its value. Drugs with long half-lives may require a loading dose to achieve therapeutic plasma concentrations rapidly. It takes about 4.5 half-lives to reach steady state plasma levels. Most drugs follow first order kinetics, where a constant fraction of the drug in the body is eliminated per unit time. However, some drugs may follow zero order kinetics, where the plasma concentration of the drug decreases at a constant rate, despite the concentration of the drug. For drugs with nonlinear kinetics of dose-dependent kinetics, the relationship between the AUC of CSS and dose is not linear, and the kinetic parameters may vary depending on the administered dose.

Historical Classification of Schizophrenia

The classification of schizophrenia has evolved over time, with various individuals contributing to its development. In 1801, Phillippe Pinel used the term ‘demencé’ to describe the loss of mental abilities in chronically ill patients. Benedict Morel coined the term ‘demencé precocé’ in 1852 to describe young patients with premature dementia. Kahlbaum was the first to describe ‘paraphrenia hebetica’ in the 1860s, which was later elaborated as ‘hebephrenia’ by Hecker in 1871.

In 1893, Emil Kraepelin used the term dementia praecox to describe the condition, emphasizing the importance of delusions, hallucinations, impaired attention, thought incoherence, stereotyped movements and expressions, deterioration of emotional life, and a loss of drive as key symptoms. In 1908, Eugen Bleuler coined the term ‘schizophrenia’ to replace dementia praecox, denoting ‘a splitting of the psychic functions.’ Bleuler expanded the concept to include presentations that did not include a ‘terminal state.’

Bleuler introduced a distinction between basic and accessory symptoms and primary and secondary symptoms. Basic symptoms are necessarily present in any case of schizophrenia, while accessory symptoms may of may not occur. The fundamental features of schizophrenia were loosening of associations, disturbances of affectivity, ambivalence, and autism. The alteration of associations is the only symptom that Bleuler regarded as both basic and primary, and can thus be described as the core disturbance in the Bleulerian conception of schizophrenia.

In 1939, Langfeldt introduced the term ‘schizophreniform psychosis’ to describe patients with Bleulerian schizophrenia who did not follow a progressively deteriorating course. In the 1960s, Rado/Meehl introduced the term ‘schizotypy’ to recognize the concept of a continuum of spectrum of schizophrenia-related phenotypes. In the 1980s, Crow proposed a subclassification of schizophrenia, dividing patients into types I and II. Type I patients present with positive symptoms such as delusions and hallucinations, while type II patients present with negative symptoms such as affective flattening and poverty of speech.

Sulpiride belongs to the substituted benzamide class of drugs.
Chlorpromazine falls under the phenothiazine category.
Flupentixol is classified as a thioxanthene medication.
Haloperidol is a butyrophenone compound.
Pimozide is a diphenylbutylpiperidine drug.

The half-life of a drug is the time taken for its concentration to fall to one half of its value. Drugs with long half-lives may require a loading dose to achieve therapeutic plasma concentrations rapidly. It takes about 4.5 half-lives to reach steady state plasma levels. Most drugs follow first order kinetics, where a constant fraction of the drug in the body is eliminated per unit time. However, some drugs may follow zero order kinetics, where the plasma concentration of the drug decreases at a constant rate, despite the concentration of the drug. For drugs with nonlinear kinetics of dose-dependent kinetics, the relationship between the AUC of CSS and dose is not linear, and the kinetic parameters may vary depending on the administered dose.

It is important to note that there is no collateral history available and the duration of the observed behaviour pattern is unknown. Additionally, the individual’s excessive panting and pacing may indicate motor over-activity, which is consistent with symptoms of mania. Therefore, it is necessary to consider the possibility of a drug-induced state as a potential differential diagnosis. However, until further information is obtained, it is crucial to treat this as an episode of mania.

Weight gain is a common side effect of antipsychotic medications, which may be caused by various mechanisms such as 5HT2c and H1 antagonism, hyperprolactinaemia, and increased serum leptin. This weight gain is often due to increased food intake and reduced energy expenditure. Additionally, antipsychotic-induced weight gain can lead to diabetes mellitus, with females being more susceptible to metabolic side effects than males. Among antipsychotics, clozapine and olanzapine have the highest risk of weight gain, while quetiapine and risperidone have a moderate risk. On the other hand, aripiprazole, asenapine, and amisulpride (the 3 As) are associated with the least amount of weight gain.

Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

Phenelzine is the most commonly prescribed MAOI in the UK and is considered the safest among the MAOIs. Tranylcypromine and isocarboxazid are the other MAOIs that are licensed for use. Perphenazine and pericyazine are typical antipsychotics, while promazine is less effective when taken orally and is related to chlorpromazine. Promethazine, also known as Phenergan, is a sedating antihistamine.

Antidepressants with Active Metabolites

Many antidepressants have active metabolites that can affect the body’s response to the medication. For example, amitriptyline has nortriptyline as an active metabolite, while clomipramine has desmethylclomipramine. Other antidepressants with active metabolites include dosulepin, doxepin, imipramine, lofepramine, fluoxetine, mirtazapine, trazodone, and venlafaxine.

These active metabolites can have different effects on the body compared to the original medication. For example, nortriptyline is a more potent inhibitor of serotonin and norepinephrine reuptake than amitriptyline. Similarly, desipramine, the active metabolite of imipramine and lofepramine, has a longer half-life and is less sedating than the original medication.

It is important for healthcare providers to be aware of the active metabolites of antidepressants when prescribing medication and monitoring patients for side effects and efficacy.

SSRIs, of selective serotonin reuptake inhibitors, are the first-line treatment for depression in most patients. However, some SSRIs have different side effects and interactions than others. For example, fluoxetine, fluvoxamine, and paroxetine have a higher propensity for drug interactions, while citalopram is useful for elderly patients as it is associated with lower risks of drug interactions. SSRIs should be used with caution in children and adolescents, and fluoxetine is the drug of choice in this population.

Common side effects of SSRIs include gastrointestinal symptoms, sedation, and sexual dysfunction. Paroxetine is considered the most sedating and anticholinergic, while vortioxetine is associated with the least sexual dysfunction. Patients taking SSRIs are at an increased risk of gastrointestinal bleeding, and a proton pump inhibitor should be prescribed if they are also taking an NSAID.

When stopping a SSRI, the dose should be gradually reduced over a 4 week period, except for fluoxetine. Paroxetine has a higher incidence of discontinuation symptoms, which can include mood changes, restlessness, difficulty sleeping, and gastrointestinal symptoms.

SSRIs can also have interactions with other medications, such as NSAIDs, warfarin/heparin, aspirin, and triptans. Patients should be reviewed by a doctor after starting antidepressant therapy, and if they make a good response, they should continue treatment for at least 6 months after remission to reduce the risk of relapse.

In patients who have had a myocardial infarction, approximately 20% develop depression. SSRIs are the preferred antidepressant group post-MI, but they can increase the bleeding risk, especially in those using anticoagulation. Mirtazapine is an alternative option, but it too is associated with bleeding. The SADHART study found sertraline to be a safe treatment for depression post-myocardial infarction.

Dextromethorphan is a medication used to suppress coughing and is commonly found in various cold and cough remedies available without a prescription. It is important to note that it can interact with MAOIs, which are a type of medication used to treat depression and other mental health conditions.

MAOIs: A Guide to Mechanism of Action, Adverse Effects, and Dietary Restrictions

First introduced in the 1950s, MAOIs were the first antidepressants introduced. However, they are not the first choice in treating mental health disorders due to several dietary restrictions and safety concerns. They are only a treatment option when all other medications are unsuccessful. MAOIs may be particularly useful in atypical depression (over eating / over sleeping, mood reactivity).

MAOIs block the monoamine oxidase enzyme, which breaks down different types of neurotransmitters from the brain: norepinephrine, serotonin, dopamine, as well as tyramine. There are two types of monoamine oxidase, A and B. The MOA A are mostly distributed in the placenta, gut, and liver, but MOA B is present in the brain, liver, and platelets. Selegiline and rasagiline are irreversible and selective inhibitors of MAO type B, but safinamide is a reversible and selective MAO B inhibitor.

The most common adverse effects of MAOIs occurring early in treatment are orthostatic hypotension, daytime sleepiness, insomnia, and nausea; later common effects include weight gain, muscle pain, myoclonus, paraesthesia, and sexual dysfunction.

Pharmacodynamic interactions with MAOIs can cause two types of problem: serotonin syndrome (mainly due to SSRIs) and elevated blood pressure (caused by indirectly acting sympathomimetic amines releasers, like pseudoephedrine and phenylephrine). The combination of MAOIs and some TCAs appears safe. Only those TCAs with significant serotonin reuptake inhibition (clomipramine and imipramine) are likely to increase the risk of serotonin syndrome.

Tyramine is a monoamine found in various foods, and is an indirect sympathomimetic that can cause a hypertensive reaction in patients receiving MAOI therapy. For this reason, dietary restrictions are required for patients receiving MAOIs. These restrictions include avoiding matured/aged cheese, fermented sausage, improperly stored meat, fava of broad bean pods, and certain drinks such as on-tap beer. Allowed foods include fresh cottage cheese, processed cheese slices, fresh packaged of processed meat, and other alcohol (no more than two bottled or canned beers of two standard glasses of wine, per day).

Drug-Induced Mania: Evidence and Precipitating Drugs

There is strong evidence that mania can be triggered by certain drugs, according to Peet (1995). These drugs include levodopa, corticosteroids, anabolic-androgenic steroids, and certain classes of antidepressants such as tricyclic and monoamine oxidase inhibitors.

Additionally, Peet (2012) suggests that there is weaker evidence that mania can be induced by dopaminergic anti-Parkinsonian drugs, thyroxine, iproniazid and isoniazid, sympathomimetic drugs, chloroquine, baclofen, alprazolam, captopril, amphetamine, and phencyclidine.

It is important for healthcare professionals to be aware of the potential for drug-induced mania and to monitor patients closely for any signs of symptoms. Patients should also be informed of the risks associated with these medications and advised to report any unusual changes in mood of behavior.

Multiple Sclerosis: An Overview

Multiple sclerosis is a neurological disorder that is classified into three categories: primary progressive, relapsing-remitting, and secondary progressive. Primary progressive multiple sclerosis affects 5-10% of patients and is characterized by a steady progression with no remissions. Relapsing-remitting multiple sclerosis affects 20-30% of patients and presents with a relapsing-remitting course but does not lead to serious disability. Secondary progressive multiple sclerosis affects 60% of patients and initially presents with a relapsing-remitting course but is then followed by a phase of progressive deterioration.

The disorder typically begins between the ages of 20 and 40 and is characterized by multiple demyelinating lesions that have a preference for the optic nerves, cerebellum, brainstem, and spinal cord. Patients with multiple sclerosis present with a variety of neurological signs that reflect the presence and distribution of plaques. Ocular features of multiple sclerosis include optic neuritis, internuclear ophthalmoplegia, and ocular motor cranial neuropathy.

Multiple sclerosis is more common in women than in men and is seen with increasing frequency as the distance from the equator increases. It is believed to be caused by a combination of genetic and environmental factors, with monozygotic concordance at 25%. Overall, multiple sclerosis is a predominantly white matter disease that can have a significant impact on a patient’s quality of life.

Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

Depersonalisation is a distressing condition that is solely based on an individual’s perception. It affects one’s auditory and tactile senses, as well as causing a sense of emptiness in their thoughts. Despite this, the person’s awareness remains intact, and they may experience an increased sense of self-awareness.