Monoamine oxidase inhibitors MAO

Treatment of Major Depression. Dmgs commonly used for the treatment of depressive disorders can be classified heuristicaHy iato two main categories first-generation antidepressants with the tricycHc antidepressants (TCAs) and the irreversible, nonselective monoamine—oxidase (MAO) inhibitors, and second-generation antidepressants with the atypical antidepressants, the reversible inhibitors of monoamine—oxidase A (RIMAs), and the selective serotonin reuptake inhibitors (SSRIs). Table 4 fists the available antidepressants. 

The COMT inhibitors should not be administered with the monoamine oxidase (MAO) inhibitors (see Chap. 31) because there is an increased risk of toxicity. If the COMT inhibitors are administered with norepinephrine, dopamine, dobutamine, methyldopa, or epinephrine, there is a risk of increased heart rate, arrhythmias, and excessive blood pressure changes. 

Monoamine oxidase (MAO) inhibitors. Drugs that produce inhibition of... 

Dizziness, vertigo, nausea, vomiting, constipation, and lethargy are all relatively common adverse events. These effects are more pronounced for several days after initiation and following upward dose titration. Seizures have been reported rarely the risk is dose-related and appears to increase with concomitant use of antidepressants, such as tricyclic antidepressants or selective serotonin reuptake inhibitors. Tramadol should be avoided in patients receiving monoamine oxidase (MAO) inhibitors because tramadol inhibits the uptake of norepinephrine and serotonin. 

There are numerous antidepressant medications on the market (table 7.1). Following development of monoamine oxidase (MAO) inhibitors were tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), and several atypical antidepressants (Baldessarini 1996). Successive generations of antidepressants have not necessarily become more effective in treating depression, but rather offer more favorable side-effect profiles—a crucial factor in effective clinical pharmacotherapy. An effective medication is not useful if its side effects are intolerable. 

Yamada N, Takahashi S, Todd KG, Baker GB, Paetsch PR. 1993. Effects of two substituted hydrazine monoamine oxidase (MAO) inhibitors on neurotransmitter amines, y-aminobutyric acid, and alanine in rat brain. J Pharm Sci 82 934. 

Figure 2.18. The major pathway leading to the synthesis and metabolism of 5-hydroxytryptamine (5-HT). Metabolism of tryptophan to tryptamine is a minor pathway which may be of functional importance following administration of a monoamine oxidase (MAO) inhibitor. Tryptamine is a trace amine. L-Aromatic amino acid decarboxylase is also known to decarboxylate dopa and therefore the term "L-aromatic amino acid decarboxylase" refers to both "dopa decarboxylase"...

The first drug-drug interaction alert issued by the Committee in 1966 concerned the risks from interactions between preparations containing adrenaline or noradrenaline and monoamine oxidase (MAO) inhibitors used for the treatment of depression. 

Advanced arteriosclerosis symptomatic cardiovascular disease moderate to severe hypertension hyperthyroidism hypersensitivity or idiosyncrasy to the sympathomimetic amines glaucoma agitated states history of drug abuse during or within 14 days following administration of monoamine oxidase (MAO) inhibitors (hypertensive crises may result). 

Hypersensitivity to cyclobenzaprine concomitant use of monoamine oxidase (MAO) inhibitors or within 14 days after their discontinuation acute recovery phase of Ml and in patients with arrhythmias, heart block, or conduction disturbances or CHF hyperthyroidism. 

Monoamine oxidase (MAO) inhibitors MAO and COMT are the 2 major enzyme systems involved in the metabolism of catecholamines. Do not treat patients concomitantly with entacapone and a nonselective MAO inhibitor. 

Coadministration with a monoamine oxidase (MAO) inhibitor, Wellbutrin, Wellbutrin SR or any medications that contain bupropion current or prior diagnosis of bulimia or anorexia nervosa, seizure disorders patients who have shown an allergic response to bupropion or other ingredients in the formulation patients undergoing abrupt discontinuation of alcohol or sedatives (including benzodiazepines). 

Monoamine oxidase (MAO) inhibitors block the oxidative deamination of monoamines, i.e. norepinephrine and serotonin by inhibiting monoamine oxidase type A (MAO-A) and dopamine also by monoamine oxidase type B (MAO-B) inhibition, thereby increasing these neurotransmittors at their receptors in the brain and in the periphery. MAO-A... 

Fig. 2. isozyme seiectivity of fluoroaiiyi amine monoamine oxidases (MAO) inhibitors. The seiectivity ratio was defined as the ratio of the concentrations of inhibitors required to decrease the activity of both forms of the enzyme at the same rate [77]. A high ratio thus indicates a B-seiective inhibitor. 

Contraindications Concurrent use of monoamine oxidase (MAO) inhibitor therapy, hypersensitivity to brimonidine or any other component of the formulation... 

This was put forward in 1965 by J. Schildkraut and states that some, if not all, depressions are the consequence of an absolute or relative deficiency of catecholamines, particularly norepinephrine, at functionally important adrenergic receptor sites in the brain (Schildkraut, 1965, p. 509). The evidence brought forward in support of this hypothesis was impressive (Table 4.2) because it covered both clinical and multifarious pharmacological findings. The antidepressant effect of imipramine and of the monoamine oxidase (MAO) inhibitors was attributed to the fact that these medicaments bring about an increased supply of functionally available catecholamines at the synapse ... 

The QSAR analysis of the monoamine oxidase (MAO) inhibitors by Kutter and Hansch is one of the earliest successes in the application of Es constante). They... 

In this chapter, we will review pharmacological concepts underlying the use of several classes of antidepressant drugs, including the classical monoamine oxidase (MAO) inhibitors, the classical tricyclic antidepressants, the popular serotonin selective reuptake inhibitors (SSRIs), and the new selective noradrenergic reuptake... 

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