Chloral hydrate
Chloral hydrate has a narrow therapeutic index and is not recommended for the treatment of insomnia.8 Tolerance to its effects develops after only 2 weeks of use, and drug interactions with warfarin can occur.2
Over-the-counter sleep aids
Most over-the-counter sleep aids contain diphen-hydramine, a long-acting antihistamine that is considered less effective than benzodiazepines. The anticholinergic properties of antihistamines can result in cognitive changes and urinary retention in the elderly.8 Melatonin and valerian are “natural” hypnotics that are available without a prescription,9 but their safety and efficacy are not regulated by the FDA.8
Antidepressants
Antidepressants with sedative effects, such as tricyclic antidepressants and trazodone, have been used for insomnia, but minimal data support the efficacy or safety of this approach.8 Tricyclic antidepressants may exacerbate restless legs syndrome and periodic limb movement disorder,8 cause anticholinergic side effects, worsen chronic heart failure, and cause ortho-static hypotension and falls.2 Although tra-zodone is not a tricyclic antidepressant, it can cause dry mouth, orthostatic hypotension, and (rarely) priapism.2
Recommendations from others
A Canadian consensus statement published in 2003 supports the use of non-benzodiazepines such as zolpidem and zaleplon due to improved tolerability, and less withdrawal and abuse potential compared with benzodiazepines.7 The National Heart, Lung and Blood Institute Working Group on Insomnia recommends the use of short-acting hypnotics for short-term management of insomnia, but does not differentiate between short-acting benzodiazepines and the newer hypnotics such as zolpidem and zale-plon.8 Geriatric experts recommend that long-acting benzodiazepines, barbiturates, and amitriptyline be avoided in the elderly due to the risk of adverse drug events.10
CLINICAL COMMENTARY
Question the patient about sleep habits
David Cravens, MD, MSPH
Department of Family & Community Medicine, University of Missouri–Columbia
Sleep complaints are common in the elderly. However, before prescribing a hypnotic, determine the elderly patient’s sleep habits: often daytime naps plus nighttime sleep add up to adequate sleep. Encourage measures to avoid daytime naps if nighttime sleep is more important. Second, discuss sleep hygiene, such as avoiding evening caffeine or excessive alcohol, and avoiding using bed for activities other than sleeping, such as watching TV, reading, and the like. Determine whether sleep problems are part of a larger problem requiring evaluation, such as medication effects, depression, or obstructive sleep apnea. Finally, consider costs: although not a true hypnotic, trazodone at doses of 25–50 mg is a very effective and well-tolerated soporific at about one-tenth the cost of 5 mg of zolpidem or zaleplon.