Monoamine oxidase inhibitors selective

Tricyclic antidepressants Monoamine oxidase inhibitors Selective serotonin reuptake inhibitors Antipsychotics Phenothiazines Risperidone Lithium... 

Contents Introduction, history and brain basics—Older antidepressants tricyclics and monoamine oxidase inhibitors—Selective serotonin reuptake inhibitors—Second generation antidepressants—Lithium, a medication for bipolar depression—Natural depressants—Teens and antidepressants trends and attitudes—Case study one girl s experience with antidepressants. 

Monoamine Oxidases and their Inhibitors. Table 4 Nonselective and selective monoamine oxidase inhibitors... 

MAOI, monoamine oxidase inhibitor SSRI, selective serotonin reuptake inhibitor TCA, tricyclic antidepressant. 

MAOI, monoamine oxidase inhibitor SARI, serotonin antagonist and reuptake inhibitor SNRI, serotonin and norepinephrine reuptake inhibitor SSRI, selective serotonin reuptake inhibitor TCA, tricyclic antidepressant. 

MAO (monoamine oxidase) inhibitor Non-selective inhibitors of the enzyme monoamine oxidase. An example is iproniazid, one of the first-generation anti-... 

A number of medications used in the treatment of anxiety have effects on serotonin neurotransmission (Ch. 13). These medications include tricyclic antidepressant medications, SSRIs, and monoamine oxidase inhibitors (MAOIs). However, because these medications take weeks to exert their full anxiolytic effects, it is unlikely that blocking the reuptake (and thus increasing synaptic levels) of either serotonin or norepinephrine selectively is responsible for their anxiolytic properties — rather it is suspected that the therapeutic effects are due to changes in gene expression, protein levels, and eventually changes in synaptic connections between neurons. 

Phentermine (30 mg in the morning or 8 mg before meals) has less powerful stimulant activity and lower abuse potential than amphetamines and was an effective adjunct in placebo-controlled studies. Adverse effects (e.g., increased blood pressure, palpitations, arrhythmias, mydriasis, altered insulin or oral hypoglycemic requirements) and interactions with monoamine oxidase inhibitors have implications for patient selection. 

Clover V, Liebowitz J, Armando I, Sandler M. (1982). beta-Carbolines as selective monoamine oxidase inhibitors in vivo implications. J Neurai Transm. 54(3-4) 209-18. 

Villegier AS, Salomon L, et al (2006) Monoamine oxidase inhibitors allow locomotor and rewarding responses to nicotine. Neuropsychopharmacology 31(8) 1704-1713 von Ziegler NI, Schlumpf M, et al (1991) Prenatal nicotine exposure selectively affects perinatal forebrain aromatase activity and fetal adrenal function in male rats. Brain Res Dev Brain Res 62(1) 23-31... 

Listing of antidepressants in traditional groupings. Abbreviations TCAs = tricyclic antidepressants MAOls = monoamine oxidase inhibitors SSRls = selective serotonin reuptake inhibitors. 

Several different types of serotonin receptor (for example, S-HTi / 5-HT2A/ 5-HT2C/ 5-HTib/id) have been associated with the motor side effects of the SSRIs which may arise should these drugs be administered in conjunction with a monoamine oxidase inhibitor. The 5-HT3 receptor is an example of a non-selective cation charmel receptor which is permeable to both sodium and potassium ions and, because both calcium and magnesium ions can modulate its activity, the 5-HT3 receptor resembles the glutamate-NMDA receptor. Antagonists of the 5-HT3 receptor, such as ondansetron, are effective antiemetics and are particularly useful when... 

Serendipity has played a major role in the discovery of most classes of psychotropic drugs. For example, the observation that the first antidepressants, the tricyclic antidepressants and the monoamine oxidase inhibitors, impeded the reuptake of biogenic amines into brain slices, or inhibited their metabolism, following their acute administration to rats, provided the experimenter with a mechanism that could be easily investigated in vitro. Such methods led to the development of numerous antidepressants that differed in their potency, and to some extent in their side effects (for example, the selective serotonin reuptake inhibitors) but did little to further the development of novel antidepressants showing greater therapeutic efficacy. The accidental discovery of atypical antidepressants such as mianserin led to the broadening of the basis of the animal models... 

Obsessive compulsive disorder in an 8-year-old can be treated using fluvoxamine (selective serotonin reuptake inhibitor, SSRI). It is usually administered initially os 25 mg daily, and increased if necessary in steps of 25 mg every 4-7 days to a maximum of 200 mg daily. If there is no improvement within 10 weeks, treatment should be reconsidered. A selective serotonin reuptake inhibitor should not be started until 2 weeks after stopping a monoamine oxidase inhibitor (MAOl), and conversely a MAOl should not be started until at least a week after an SSRI has been stopped. 

Citalopram is a selective serotonin re-uptoke inhibitor (SSRI). These tend to have fewer ontimuscarinic effects than tricyclic antidepressant (TCA) drugs, such as dry mouth and constipation however, SSRIs tend to cause gastrointestinal effects, such as nausea and vomiting. MAOIs are monoamine oxidase inhibitors. 

Lorazepam is a short-acting benzodiazepine indicated for use in relieving anxiety and insomnia. Lorazepam may also be administered perioperatively to alleviate pain and in status epilepticus. Imipramine is a tricyclic antidepressant, paroxetine is a selective serotonin re-uptake inhibitor, venlafaxine is a serotonin and adrenaline re-uptake inhibitor and moclobemide is a reversible monoamine oxidase inhibitor. Imipramine, paroxetine, venlafaxine and moclobemide are all classified as antidepressants. 

Side effects, mainly due to serotonin reuptake inhibition include G1 upset, nervousness, and sexual dysfunction. SSRls are associated with an increased risk of falls. Hyponatraemia due to SIADH is an uncommon, but important side effect in elderly patients. Selective serotonin and norepinephrine reuptake inhibitors (S SNRls) such as venlafaxine and duloxetine are also useful in older patients. Other heterocyclic antidepressants of importance in older patients because of relative safety include bupro-prion and mirtazepine. They are reserved for patients with resistance to or intolerance of SSRls. Currently, trazodone is used mostly for sleep disturbance in depression in doses of 50-100 mg at bedtime. The monoamine oxidase inhibitors phenelzine. 

Dmg-induced serotonin syndrome is generally mild and resolves when the offending drugs are stopped. However, it can be severe and deaths have occurred. A large number of drugs have been implicated including tricyclic antidepressants, monoamine oxidase inhibitors (MAOIs), selective serotonin re-uptake inhibitors (SSRIs), pethidine, lithium, and dextromethorphan. The most severe type of reaction has occurred with the combination of selective serotonin re-uptake inhibitors and monoamine oxidase inhibitors. Both non-selective MAOIs such as phenelzine and selective MAOIs such as moclobemide and selegiline have been implicated. 

The triptans should be used with caution in patients on lithium, monoamine oxidase inhibitors or selective serotonin reuptake inhibitors, due to the rare occurrence of the serotonin syndrome. 

Some selective serotonin re-uptake inhibitors are powerful inhibitors of cytochrome P450 enzymes and the metabolism of e.g. tricyclic antidepressants can be inhibited resulting in serious toxicity. Additive sedation can be expected when given in combination with CNS depressants such as benzodiazepines but also with alcohol. Selective serotonin re-uptake inhibitors should not be used in combination with monoamine oxidase inhibitors as fatal reactions have been reported. 

Examples of monoamine oxidase inhibitors are phenelzine, tranylcypromine, isocarboxazid and mo-clobemide. They are indicated for atypical depression. Changes in the neurotransmitter levels are seen in several days but the clinical effect may lag by several weeks. Phenelzine is a non-selective hydrazine-type monoamine oxidase inhibitor while the also non-selective inhibitor tranylcypromine is of the non-hydrazine-type. Phenelzine, tranylcypromine and isocarboxazid are irreversible inhibitors. Phenelzine is partly metabolized by acetylation and slow acetylators are more prone to toxicity. It has anxiolytic properties and superior efficiacy in treating severe anxiety. 

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