Effectiveness of intermediate-term use of secobarbital.

Secobarbital, 100 mg, was evaluated in two separate sleep laboratory drug evaluation studies, each with 4 insomniac patients. In both studies, the effect of secobarbital in inducing and maintaining sleep was evaluated, as well as the effects of the drug on sleep stages. Statistical analysis demonstrated that the results of the two studies could be combined. With short-term drug administration of secobarbital (up to 3 nights), there was an improvement in both sleep induction and sleep maintenance. Total wake time was decreased 43% below baseline and was consistently decreased in each third of the night. With intermediate-term drug administration (2 wk), total wake time was decreased only 14% (not statistically significant). Following drug withdrawal, the degree of sleep difficulty returned to baseline levels. The results indicate that secobarbital 100 mg is effective for short-term use but loses much of its effectiveness with intermediate use and suggest that the drug is of limited value for insomniac patients who require nightly medication beyond a period of 1 wk. With short-term administration, secobarbital induced a slight decrease in rapid eye movement (REM) and slow-wave sleep and a significant increase in stage 2 sleep. With intermediate administration, sleep stage values were similar to baseline levels. Following withdrawal, there was only a minimal increase in REM sleep above baseline levels, a significant increase in stage 3 sleep, and a significant decrease in stage 2 sleep. The rebound increase in stage 3 sleep is similar to that reported following withdrawal of pentobarbital.