Sleep
Insomnia is a general term for difficulty falling asleep and/or staying asleep. Insomnia is the most common sleep problem, with many adults reporting occasional insomnia, and 10–15% reporting a chronic condition. Insomnia can have many different causes, including psychological stress, a poor sleep environment, an inconsistent sleep schedule, or excessive mental or physical stimulation in the hours before bedtime. Insomnia is often treated through behavioral changes like keeping a regular sleep schedule, avoiding stimulating or stressful activities before bedtime, and cutting down on stimulants such as caffeine. The sleep environment may be improved by installing heavy drapes to shut out all sunlight, and keeping computers, televisions and work materials out of the sleeping area.
Doxepin
The effect sizes of very low-dose doxepin in the treatment of insomnia range from small to medium. These include subjective and objective measures of sleep maintenance, sleep duration, and sleep efficiency. Conversely, very low-dose doxepin shows relatively weak effects on sleep initiation and does not significantly separate from placebo on this measure. This is in contrast to benzodiazepines and nonbenzodiazepine (Z-drug) hypnotics, which are additionally effective in improving sleep onset latency. However, it is also in contrast to higher doses of doxepin (50 to 300 mg/day), which "have" been found to significantly reduce latency to sleep onset. A positive dose–response relationship on sleep measures was observed for doses of doxepin between 1 and 6 mg in clinical studies, whereas the incidence of adverse effects remained constant across this dose range in both young and older adults. However, the incidence of adverse effects appeared to increase with longer treatment duration. A dose of doxepin as low as 1 mg/day was found to significantly improve most of the assessed sleep measures, but unlike the 3 and 6 mg/day doses, was not able to improve wake time during sleep. This, along with greater effect sizes with the higher doses, was likely the basis for the approval of the 3 and 6 mg doses of doxepin for insomnia and not the 1 mg dose.