Concomitant or recent (previous fourteen days) monoamine oxidase inhibitor use can lead to hypertensive reactions, including hypertensive crises. The antihypertensive effects of methyldopa, mecamylamine, reserpine and veratrum alkaloids may be reduced by sympathomimetics. Beta-adrenergic antagonists may also interact with sympathomimetics. Increase of ectopic pacemaker activity can occur when<unk>  is used concomitantly with digitalis. Antacids increase the rate of<unk>  absorption, while kaolin decreases it.
Pseudoephedrine
Ephedrine
Theobromine
Tesofensine
Benzoctamine
Bethanechol
Butalbital
Guaifenesin