Isocarboxazid , dosing

With most psychedelics, their activity can probably be considerably enhanced by prior (or possibly concomitant) use of a monoamine oxidase inhibitor (e.g., isocarboxazid (Marplan), nialamide (Niamid), phenelzine (Nardil), and tranylcypromine (Parnate)). Some compounds (e.g., DMT) which have no oral activity, can probably become orally active. These compounds are often prescribed as antidepressants, but it is not a good idea to use them frequently or in large doses. For antidotes to the hallucinogens see Amer. J. Hosp. Pharm. 30,80(1973). 

Increased bilirubin levels are caused due to the intake of large doses of such drugs as chloroquine, vitamin K, sulpha-drugs, tetracyclines, paracetamol, nicotinic acid and monoamine oxidase inhibitors (e.g., iproniazid RP 1.0 nialamide RP 1.8 isocarboxazid RP 3.1 phenelzine RP 18 pheniprazine RP31 and tranylcypromine RP 45), where RP designates the Relative Potency based on the tiyptamine potentiation test. The elevated levels are due to hepatic injury, and... 

Because of the limited experience with systematically monitored patients receiving isocarboxazid at the higher end of the currently recommended dose range of up to 60 mg/day, caution is indicated in patients for whom a dose of 40 mg/day is exceeded. 

Drug abuse and dependence There have been reports of drug dependency in patients using doses of tranylcypromine and isocarboxazid significantly in excess of the therapeutic range. 

In adults, phenelzine, tranylcypromine, and isocarboxazid are rapidly absorbed and have short half-lives, requiring more than once-a-day dosing. For example, the half-life of phenelzine ranges from 1.5 to 4 hours and the half-life for tranylcypromine ranges from 1.54 to 3.15 hours (Mallinger and Smith, 1991). 

Casey JF, Hollister LE, Klett CJ, et al. Combined drug therapy of chronic schizophrenics. Controlled evaluation of placebo, dextro-amphetamine, imipramine, isocarboxazid, and trifluoperazine added to maintenance doses of chlorpromazine. Am J Psychiatry 1961 117 997-1003. 

Little evidence to support efficacy of isocarboxazid af doses below 30 mg/day... 

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. 

Serious and potentially life-threatening reactions (the serotonin syndrome) can develop if venlafaxine and non-selective MAOIs (isocarboxazid, phenelzine, tranylcypromine) are given concurrently, or even sequentially if insufficient time is left in between. The situation with moclobemide, in therapeutic doses, is uncertain. 

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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