Moclobemide Sympathomimetics

In addition to this serious diet-drug interaction, irreversible MAOIs also potentiate the effects of sympathomimetic drugs like ephedrine found in over-the-counter cold remedies and recreational stimulants like amphetamine. The MAOIs also interact with drugs that increase synaptic concentrations of 5-HT, such as the tricyclic antidepressant clomipramine and the herbal SSRI antidepressant St John s wort (Hypericum spp.). The resulting serotonin syndrome is characterised by hyperthermia and muscle rigidity. While devoid of these side effects the reversible MAO-A inhibitor moclobemide has yet to establish itself as a first-line alternative to the SSRIs. 

Tyramine-rich foods, sympathomimetics, dextromethorphan, anorectics, and other antidepressants should be avoided when treating with moclobemide. It also interacts with opioid analgesics, serotonin agonists, NSAIDs, levodopa, and cimetidine.140,141... 

Moclobemide increased the pressor effect of ephedrine in healthy volunteers, who also had more adverse effects including light-headedness and palpitation (SEDA-18, 16). Thus, moclobemide can potentiate the effect of indirect sympathomimetics such combinations should be used with caution. 

Like moclobemide, toloxatone, a selective and reversible inhibitor of monoamine oxidase type A, is thought to be relatively safe in combination with sympathomimetics (SEDA-18, 16). However, sweating, tachycardia, and headache have been reported when terbutaline was added to toloxatone and phenylephrine (SEDA-18, 16). In healthy volunteers, doses up to 600 mg/day did not produce hypertensive reactions on challenge with oral tyramine (SEDA-17, 17). Two fatal cases of fulminant hepatitis have been reported (SEDA-16, 7). 

The ephedra alkaloids are all sympathomimetic amines, which means that a host of drug interactions are theoretically possible. In fact, only a handful of adverse drug interactions have been reported in the peer-reviewed literature. The most important of these involve the monoamine oxidase inhibitors (MAOI). Irreversible, nonselective MAOIs have been reported to adversely interact with indirectly acting sympathomimetic amines present in many cough and cold medicine. In controlled trials with individuals taking moclobemide, ephedrine s effects on pulse and blood pressure were potentiated, but only at higher doses than those currently provided in health supplements (137). Ephe-drine-MAOI interaction may, on occasion, be severe enough to mimic pheo-... 

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... 

MAOIs BETA-2 AGONISTS t occurrence of headache, hypertensive episodes. Unlikely to occur with moclobemide and selegiline Due to impaired metabolism of these sympathomimetic amines because of inhibition of MAO. Moclobemide is involved in the breakdown of serotonin, while selegiline is mainly involved in the breakdown of dopamine Be aware. Monitor BP closely... 

The data with high-dose ephedrine show that moclobemide is not free of this interaction, and the manufacturers of moclobemide advise avoiding sympathomimetics such as ephedrine, pseudoephedrine and phenylpropa-... 

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