The use of an inorganic salt in conjunction with an organic mercurial diuretic for the purpose of augmenting diuresis was first reported by Keith, Barrier and Whelan1 in 1925. These authors showed that a combination of ammonium chloride, administered by mouth, with injections of merbaphen may be effective in causing diuresis in patients with chronic nephritis and edema, when either substance given singly is ineffective. That ammonium chloride and certain other acid-producing salts have a diuretic action when given alone had been noted prior to that time.2 In recent years the enhancing effect of such acid-producing salts on the diuretic response to mercurial compounds has been repeatedly confirmed. Explanations, however, of the mechanism by which these salts affect the diuretic action of mercury are still at variance.
Keith and Whelan3 discussed certain effects which are noted when ammonium chloride is administered in conjunction with merbaphen or salyrgan: