the evening) of the plasma corticosteroid levels. Amphetamines may interfere with urinary steroid determination. Headache (26%), asthenia (6%), somnolence , infection , tooth disorder , speech disorder , and twitching have also been reported. References Cardiomyopathy associated with amphetamine administration. Smith HJ, Roche AH, Jausch MF, Herdson PB Am Heart J 1976;91:792-7.