Chronic medical conditions

Breathing disorders (obstructive sleep apnea)

Cancer

Circadian rhythm disorders

Dermatologic disorders (pruritus)

Endocrine conditions (diabetes mellitus, menopause, thyroid disease)

Gastrointestinal problems (heartburn, gastroesophageal reflux)

Heart failure

Ischemic heart disease

Neurologic disease (dementia)

Pain

Pulmonary disease

Restless legs syndrome

Rheumatic disease (arthritis, fibromyalgia)

Urologic disease (benign prostatic hyperplasia, nocturia)

Medications

Antidepressants

Antihypertensives

Appetite suppressants

Beta antagonists

Calcium channel blockers

Central nervous system stimulants (including caffeine)

Diuretics

Glucocorticoids

Over-the-counter allergy, cough, and cold medications

Respiratory stimulants (theophylline)

Sedatives and hypnotics

Psychiatric conditions

Anxiety

Depression

Posttraumatic stress disorder

Substance abuse

Alcohol

Illicit drugs

Tobacco