Effects of ammonium chloride on urinary pH and cigarette smoking behavior.

We determined the effects of acidification of urinary pH on cigarette smoking behavior to assess the postulated relationships between stress, urinary pH, and cigarette smoking. Urine was acidified by short-term administration of 12.5, 25, and 50 mg/kg ammonium chloride and long-term administration of 50 mg/kg ammonium chloride. Measurements of cigarette smoking behavior included the number of cigarettes smoked as well as automated measures of puff frequency and duration. Short- and long-term administration of ammonium chloride induced decreases in urinary pH but failed to induce any substantial changes in number of cigarettes smoked, puff frequency, or puff duration.