Sodium salicylamide: relative bioavailability and subjective effects.

The bioavailability of sodium salicylamide (NaSAM) in solution of salicylamide (SAM) tablets was compared in 6 healthy human volunteers. Bioavailability was assessed by plasma level determinations of nonmetabolized salicylamide (free SAM) and salicylamide plus conjugated metabolites (total SAM) for 3 hr following oral doses of 0.65, 1.30, 1.95, and 2.60 gm of salicylamide. The availability of NaSAM was found to be superior to SAM and dose-dependent. Mean peak levels of free SAM and total SAM were higher and were reached earlier after NaSAM liquid than after SAM tablets. Significantly higher mean levels of free SAM were found at the 1.95 and 2.60 gm dose levels after NaSAM administration than after SAM. Mean total SAM concentration was significantly higher after NaSAM at all dosage levels. The sedative effects of salicylamide were assessed with a self-scoring questionnaire. Sedation seemed to increase with increasing dose of both NaSAM and SAM. The sedative response occurred earlier after NaSAM than after SAM. Side effects were minor and transient in nature, occurred at the higher dosage levels, and were predominantly lightheadedness and dizziness. Because NaSAM produces higher drug levels and has a more rapid onset of subjective effects, we conclude that it represents a potentially superior dosage form.