Phenylephrine Moclobemide

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). 

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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