Selegiline Isocarboxazid

SELECTIVE MAO-B INHIBITORS Two isozymes of MAO (MAO-A and MAO-B) oxidize monoamines and both are present in the periphery and GI tract MAO-B is the predominant form in the striatum and is responsible for most of the oxidative metabolism of dopamine in the brain. At low-to-moderate doses (10 mg/day or less), selegiline (eldepryl) selectively and irreversibly inhibits MAO-B. Unlike nonspecific inhibitors of MAO (e.g., phenelzine, tranylcypromine, isocarboxazid), selegiline does not inhibit peripheral metabolism of catecholamines and can be taken safely with levodopa. Selegihne does not cause the lethal potentiation of indirectly acting sympathomimetic amines such as dietary tyramine. Doses of selegiline higher than 10 mg daily can produce inhibition of MAO-A and should be avoided. 

In the United States, the three MAOIS available for the treatment of psychiatric conditions are phenelzine (Nardil), tranylcypromine (Parnate), and isocarboxazid (Marplan). All three agents have indications for adult major depression (>16 years old) and, more specifically, atypical depression (anergia, hypersomnia, hy-perphagia, somatization, and anxiety symptoms). Although not indicated for anxiety, the MAOIs can also be particularly helpful in treatment of these disorders. Selegiline or L-deprenyl (Eldepryl) is also available in the United States and indicated for symptoms of Parkinson s disease and depression. 

Current MAOIs include the hydrazine derivatives phenelzine and isocarboxazid and the non-hydrazines tranylcypromine, selegiline, and moclobemide (the latter is not available in the USA). The hydrazines and tranylcypromine bind irreversibly and nonselectively with MAO-A and -B, whereas other MAOIs may have more selective or reversible properties. Some of the MAOIs such as tranylcypromine resemble amphetamine in chemical structure, whereas other MAOIs such as selegiline have amphetamine-like metabolites. As a result, these MAOIs tend to have substantial CNS-stimulating effects. 

Summary of some amine-containing foods which could interact with MAOIs, particularly irreversible inhibitors (e.g. phenelzine, isocarboxazid, tranycypromine, selegiline)... 

These two classes of drugs are subject to life-threatening interactions (e.g., mania, convulsions, hypertension, heart arrythmias) with monoamine oxidase (MAO) inhibitors, such as isocarboxazide, phenelzine, selegiline, and tranylcypromine, because they inhibit the metabolism of serotonin and sympathomimetic amines (19,120). This interaction is one of the earliest toxic drug-drug interactions to be recognized however, these interactions are not often observed because the MAO inhibitors are now used sparingly. 

Isocarboxazid (Marplan) Moclobemide (Aurorix, Manerix, Moclodura ) Phenelzine (Nardil) Tranylcypromine Selegiline (Selegiline, Eldepryl)... 

Quazepam Venlafaxine Amitriptyline Selegiline (deprenyl) Lithium carbonate Lithium carbcxiate controlled release Triazolam Haloperidol Propranolol Clonazepam Chlordiazepoxide Lithium carbonate slow release Lithium carbonate Lithium carbonate Loxapine Maprotiline Fluvoxamine Isocarboxazid... 

Clinically important, potentially hazardous interactions with dexibuprofen, isocarboxazid, MAO inhibitors, phenelzine, selegiline, St John s wort, sumatriptan, tramadol, tranylcypromine, trazodone... 

Clinically important, potentially hazardous interactions with alprazolam, amphetamines, astemizole, clarithromycin, clozapine, desipramine, dexibuprofen, dextroamphetamine, diethylpropion, droperidol, duloxetine, erythromycin, haloperidol, imipramine, isocarboxazid, linezolid, lithium, MAO inhibitors, mazindol, meperidine, methamphetamine, midazolam, moclobemide, nortriptyline, phendimetrazine, phenelzine, phentermine, phenylpropanolamine, phenytoin, pimozide, pseudoephedrine, selegiline, serotonin agonists, sibutramine, St John s wort, sumatriptan, sympathomimetics, tramadol, tranylcypromine, trazodone, tricyclic antidepressants, troleandomycin, tryptophan, zolmitriptan... 

Clinically important, potentially hazardous interactions with acyclovir, alcohol, amphetamines, barbiturates, CNS depressants, fluoxetine, furazolidone, general anesthetics, glycopyrrolate, glycopyrronium, isocarboxazid, linezolid, lithium, MAO inhibitors, moclobemide, phenelzine, phenobarbital, phenothiazines, rasagiline, ritonavir, selegiline, sibutramine, SSRIs, tranquilizers, tranylcypromine, tricyclic antidepressants, val acyclovir... 

Monoamine Oxidase Inhibitors Isocarboxazid, Phenelzine, Tranylcypromine, Selegiline, Moclobemide... 

MAOIs are classified as selective and non-selective and as reversible and irreversible. The main non-selective MAOIs include isocarboxazid, nialamide, tranylcypromine, and phenelzine (all irreversible). The selective MAOIs are classified as MAO-A and MAO-B inhibitors. The MAO-A selective inhibitors include befloxatone, cimoxatone, moclobemide, and toloxatone (all reversible). The MAO-B selective inhibitors include pargyline and selegiline (deprenyl) (all irreversible). 

The UK manufacturer contraindicates the concurrent use of linezolid with or within 2 weeks of taking any other drug that inhibits MAO-A or MAO-B. They specifically name the non-selective MAOIs isocarboxazid and phenelzine, the RIMA, moclobemide, and the MAO-B inhibitor, selegiline. Linezolid has reversible non-selective MAO-inhibitory activity, and this warning is based on the sometimes serious reactions that have occurred when non-selective MAOIs are given sequentially (see MAOIs + MAOIs or RIMAs , p.1137) or MAOIs are given with MAO-B inhibitors, see MAO-B inhibitors + MAOIs or RIMAs , p.692. 

Know the mechanism of action of your muscle relaxant. If the patient is already taking tramadol or tapentadol as well as amitriptyline, consider your rationale for adding a third agent with serotonergic activity such as cyclobenzaprine, as well as the increased risk of serotonin syndrome. Do not use cyclobenzaprine within 2 weeks of the last dose of an MAOI. Some MAOIs include isocarboxazid (Marplan), tranylcypromine (Parnate), phenelzine (Nardil), selegiline (Eldepryl, Emsam),... 

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