Phenylpropanolamine Amfetamine

After 5 to 10 days of use furazolidone has MAO-inhibitory activity about equivalent to that of the non-selective MAOIs. The concurrent use of furazolidone with indirectly-acting sympathomimetic amines (amfetamines, phenylpropanolamine, ephedrine, etc.) or with tyramine-rich foods and drinks may be expected to result in a potentially serious rise in blood pressure. However, direct evidence of accidental adverse reactions of this kind does not seem to have been reported. The pressor effects of noradrenaline (norepinephrine) are unchanged by furazolidone. 

Monoamine oxidase inhibitors (MAOI) are not completely selective for MAO and impair the metabolism of tricyclic antidepressants, of some sympathomimetics, e.g. phenylpropanolamine, amfetamine, of opioid analgesics, especially pethidine, and of mercaptopurine. 

The authors reviewed a number of other case reports of phenylpropanolamine-induced cerebral vasospasm associated with hemorrhages and drew a parallel with similar effects of amfetamines. 

Isolated reports describe delirium in one patient and a seizure in another when methylphenidate was taken with sertraline. Schizophrenia and symptoms of amfetamine toxicity have also been reported in two patients taking amfetamine and fluoxetine. There is an isolated report of the serotonin syndrome associated with concurrent citalopram and dexamfetamine and another associated with sertraline and etilefrine. There is also a report of adverse effects associated with fluoxetine and phenylpropanolamine. 

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