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.
Modafinil
Modafinil, sold under the brand name Provigil among others, is a medication to treat sleepiness due to narcolepsy, shift work sleep disorder, or obstructive sleep apnea (OSA). In OSA continuous positive airway pressure is the preferred treatment. While it has seen off-label use as a purported cognitive enhancer, the research on its effectiveness for this use is not conclusive. It is taken by mouth.
Common side effects include headache, anxiety, trouble sleeping, and nausea. Serious side effects may include allergic reactions such as anaphylaxis, Stevens–Johnson syndrome, abuse, or hallucinations. It is unclear if use during pregnancy is safe. The amount of medication used may need to be adjusted in those with kidney or liver problems. It is not recommended in those with an arrhythmia, significant hypertension, or left ventricular hypertrophy. How it works is not entirely clear. One possibility is that it may affect the areas of the brain involved with the sleep cycle.
Modafinil was approved for medical use in the United States in 1998. In the United States it is classified as a schedule IV controlled substance due to concerns about addiction. In the United Kingdom it is a prescription only medication. It is available as a generic medication. In the United Kingdom it costs the NHS about £105.21 a month as of 2018. In the United States the wholesale cost per month is about US$34.20 as of 2018.
Modafinil is a eugeroic used for treatment of narcolepsy, shift work sleep disorder, and excessive daytime sleepiness associated with obstructive sleep apnea.