A comparison of tyrosine against placebo, phentermine, caffeine, and D-amphetamine during sleep deprivation.

Sleep deprivation can impair alertness and cognitive and motor performance. We hypothesized that the amino acid tyrosine might reduce deleterious effects of sleep deprivation. Seventy-six healthy males, age 18-35 years, participated in a four-day protocol that included a habituation night, a baseline night, a 40.5 h period without sleep, and a recovery night. Tyrosine 150 mg/kg, caffeine 300 mg/70 kg, phentermine 37.5 mg, D-amphetamine 20 mg and placebo were administered in a double-blind, randomized fashion to compare their effects on the time it took to fall asleep, on endocrine responses during sleep deprivation, and on sleep quantity, quality and architecture as measured by polysomnography during recovery sleep. When given after 36 h without sleep, tyrosine had no significant effect on any parameter of sleep. D-amphetamine produced marked decrease in sleep drive but caused deleterious effects on many aspects of recovery sleep. Still, D-amphetamine was associated with increased alertness on the first recovery day. Phentermine and caffeine both decreased sleep drive during sleep deprivation, but phentermine impaired rapid-eye-movement (REM) recovery sleep. Tyrosine (when compared to placebo) had no effect on any sleep related measure, but it did stimulate prolactin release.

Behavioral and hypnotic treatments for insomnia subtypes.

This investigation compared progressive muscle relaxation plus cognitive distraction (PMR/CD), hypothesized to better improve sleep onset, versus sleep restriction and stimulus control (SR/SC), hypothesized to better improve sleep maintenance, versus a flurazepam (Dalmane) positive contrast condition (MED) and a sleep hygiene education minimal treatment control condition (SHE). Participants with chronic insomnia (N = 53), completed 2 baseline weeks of sleep diaries, and were randomly assigned to a treatment group for 2 more weeks. In the second phase, PMR/CD participants were assigned to 2 weeks of PMR/CD + SR/SC + SHE while SHE participants continued SHE. Results indicated that PMR/CD had greater effect upon sleep onset than SR/SC and SHE, SR/SC had greater effect on sleep maintenance than PMR/CD, and MED was better than the other treatments. In the second phase, the treatment package produced modest additional improvements and SHE performed superior to expectations.