INSOMNIA

Etiologies

Insomnia is a subjective decline in the quantity of restorative sleep despite an adequate opportunity to sleep and not secondary to direct interference from external stimuli.  Transient symptoms may occur secondary to stressful situations or tragedies which occur throughout a patient’s life, but may also occur without an identifiable stressor or may occur among travelers (“jet lag”).  These symptoms often abate once the stressful situation has passed, after an adequate period of grieving, or after a few days, respectively.  Chronic insomnia often interferes with a patient’s quality of life.  Insomnia may be a symptom of an underlying disease (propriospinal myoclonus, narcolepsy, Parkinson’s disease, sleep apnea, restless legs syndrome, chronic pain, hyperthyroidism, allergies, anxiety, depression, chronic alcoholism, drug withdrawl, asthma, or fatal familial insomnia), a medication side effect (selective serotonin reuptake inhibitors, stimulant drugs, theophylline, prednisone, felbamate, and lamotrigine), the result of excessive caffeine intake, or secondary to menopause or aging.  When insomnia is associated with an elevated energy level, bipolar disorder should be suspected and addressed.  Patients who work abnormal time shifts are also predisposed to insomnia.  Polysomnography may be indicated when the diagnosis is in doubt or when a primary sleep disorder is a possible etiology; however, most cases are diagnosed clinically from the history.  Actigraphy is another technique that may be useful in the evaluation of insomnia.

     Patients often do not discuss their sleep problems with a physician unless the subject is first addressed by the physician.  All patients who suffer from insomnia should be screened for the possibility of a medication side effect.  If this is considered unlikely or the offending medication cannot be discontinued, then the patient should be counseled regarding sleep hygiene techniques.  Patients should be counseled to: allow one hour before bedtime to relax, only lie down when sleep is possible and arise if sleep seems impossible, schedule their sleep period with bedtime and wake up at the same hours every day, use the bed only for sleeping and sex, exercise regularly to induce fatigue, avoid ingestion of stimulants, and avoid excessive daytime napping.  A bedtime snack may help some patients fall asleep; however, large meals before bedtime should be avoided.  Patients should be encouraged to record a sleep journal and to bring it in for review each visit.  A sedentary lifestyle has become common in today’s society, exercise serves to make patients fatigued and more prone to sleep and should be strongly encouraged secondary to associated improvements in the patients overall health.

     If insomnia still persists after good sleep habits as outlined above, then drug therapy should be considered.  First generation antihistamines may be useful but tolerance may develop after a few weeks and side effects often limit patient satisfaction and compliance.  Valerian and melatonin are two alternative therapies that patients may have tried prior to seeking medical advise.  Chloral hydrate may prove effective for the first two weeks but then tolerance develops.  Chloral hydrate can be associated with gastric, renal, hepatic and cardiac toxicity as well as fatal overdosage and therefore is rarely used.  Tricyclic antidepressants may be employed.  The secondary amines are not as effective as the tertiary amines at treating insomnia but are associated with fewer anticholinergic side effects.  Other antidepressants which may be effective in the treatment of insomnia include nefazodone, trazodone, and mirtazapine.  Benzodiazepines, especially the intermediate acting ones, are an effective alternative for the treatment of insomnia but the risk of dependency is great with this class of drugs.  Benzodiazepines should be used for no more than a 4 week period.  Zolpidem tartrate (Ambien 5-10 mg QHS) and zaleplon (Sonata) are two drugs used in the treatment of insomnia and are considered very effective for the treatment of chronic insomnia.  Clonidine HCl or estrogen replacement therapy may prove effective for menopause-related insomnia.  When bipolar disorder is suspected, mood stabilizers such as tegretol or valproic acid may prove useful; however, the second generation antipsychotics are very effective for treating insomnia as is lithium.