What side effects and drug interactions are there with OTC asthma medicines?
Ephedrine poses a greater chance of causing adverse drug effects or drug interactions than epinephrine because it must be absorbed into the body to be effective. Nervousness, sleeplessness, anxiety, nausea, reduced appetite, rapid heart beat, tremors (the “shakes”), and urinary retention are the most common adverse effects. Immediate medical attention may be necessary for these side effects. Monoamine oxidase inhibitors (phenelzine, isocarboxazid), clonidine, selegiline, guanethidine, and ergotamines (ergotamine tartrate, dihydroergotamine mesylate) may increase blood pressure when used at the same time as ephedrine. Methyldopa or reserpine may reduce ephedrine levels in the blood and thereby lessen the effectiveness of ephedrine. Tricyclic antidepressants (desipramine, amitriptyline, doxepin, and imipramine) may block the effect of ephedrine. The carbonic anydrase inhibitors acetazolamide and dichlorphenamide may raise ephedrine blood levels and increase the risk of side effects from
