Twelve normal volunteer subjects were given amitriptyline, fluoxetine and placebo in clinically relevant doses, each for a period of 7 days. A minimum of 28 days intervened between each drug treatment. 2. A battery of physiological, psychomotor and subjective tests was administered before drugs and on days 4 and 8. 3. On day 8 a measured dose of alcohol was given and the tests repeated 1 hour and 3 hours later. 4. Before alcohol, little effect was shown on physiological or psychomotor activity. Subjective ratings indicated that amitriptyline was less-well tolerated than fluoxetine. 5. Significant differences were found for many measures after alcohol but there were few differences with respect to the drugs.