[...] There is an interesting, and potentially informative, convergence of the metabolite of one drug with the structure of another. Under 4-MA, mention was made of a bronchodilator that has been widely used in the treatment of asthma and other allergenic conditions. This compound, 2-methoxy-N-methylamphetamine is known by the generic name of methoxyphenamine, and a variety of trade names with Orthoxine (Upjohn) being the best known. The typical dosage of methoxyphenamine is perhaps 100 milligrams, and it may be used several times a day. It apparently produces no changes in blood pressure and only a slight cardiac stimulation. And one of the major metabolites of it in man is the analogue with a hydroxyl group at the 5-position of the molecule. This phenolic amine, 5-hydroxy-2-methoxy-N-methylamphetamine is just a methyl group away from METHYL-DMA; it could either be methylated to complete the synthesis, or METHYL-DMA could be demethylated to form this phenol. There is plentiful precedent for both of these reactions occuring in the body. It is always intriguing when drugs which show distinctly different actions can, in principle, intersect metabolically at a single structure. One wonders just what the pharmacology of that common intermediate might be. [...]