Moclobemide Ephedrine

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. 

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. 

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-... 

Dingemanse J, Guentert T, Gieschke R, Stabl M. Modification of the cardiovascular effects of ephedrine by the reversible monoamine oxidase A-inhibitor moclobemide. J Cardiovasc Pharmacol 1996 28(6) 856—861. 

Clinically important, potentially hazardous interactions with carbidopa, citalopram, doxepin, ephedra, ephedrine, escitalopram, fluoxetine, fluvoxamine, levodopa, meperidine, moclobemide, nefazodone, oral contraceptives, paroxetine, sertraline, venlafaxine... 

No interaction was seen in subjects taking brofaromine 75 mg twice daily for 10 days when given 75 mg of slow-release phenylpropanolamine (Acutrim Late Day), but immediate-release phenylpropanolamine in gelatin capsules caused a 3.3-fold increase in pressor sensitivity. The pressor effects of high-dose oral ephedrine (two doses of 50 mg with a 4-hour interval) in 11 healthy subjects taking moclobemide 300 mg twice daily were increased about three to fourfold, and this resulted in an increase in palpitations and headache. ... 

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-... 

A study in 7 healthy subjects found that moclobemide 100 mg three times daily for one week had no effect on the increase in blood pressure induced by intravenous phenylephrine. Another study reported similar results. However, when moclobemide was given in a dose of200 mg three times daily for up to 3 weeks the blood pressure response to infusions of phenylephrine was increased by up to 1.8-fold. In one patient taking moclobemide (dose withheld on the morning of surgery), ephedrine and phenylephrine were used successfully and uneventfully to control hypotension during anaesthesia. ... 

Martyr JW, Orlikowski CEP. Epidural anaesthesia, ephedrine and phenylephrine in a patient taking moclobemide, a new monoamine oxidase inhibitor. Anaesthesia 996) 51, 1150-2. 

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