Drug-Induced Neurologic Conditions

Tammie Lee Demler, BS, PharmD, MBA, BCPP


US Pharmacist. 2014;39(1):47-52. 

In This Article


Insomnia is a common sleep disorder that is more prevalent in women and elderly people. Prevalence estimates vary based on specific definitions, assessment procedures, and patients studied; however, population-based studies indicate that about 30% of adults have experienced some degree of insomnia. Insomnia is a common complaint in primary care offices, with up to 40% of patients who seek intervention reporting significant sleep disturbances. Insomnia can be caused by medical conditions, but it is often a neurologic side effect of drugs.[9]

Patients with insomnia may report trouble falling asleep, difficulty staying asleep, or waking up too early. No matter which sleep phase is impacted, all patients with insomnia report poor quality of sleep overall. Normal sleep architecture consists of non–rapid eye movement (REM) sleep and REM sleep, which cycle throughout the night. Insomnia, a disruption of this sleep architecture, reduces a patient's quality of life, increases the risk of comorbid medical and psychiatric illness, and poses an increased risk of accidental injury and/or death as a result of reduced ability to perform cognitive tasks. Stimulants are well known to cause insomnia; however, other drugs, including antidepressants, corticosteroids, beta agonists, and antiparkinsonian agents, also should be evaluated when a treatment plan for insomnia is being developed.[3,10]

Once the provider identifies a potential drug contribution, it is prudent to remove the offending agent, if possible. When discontinuation is not indicated, lowering the dosage, administering the dose early in the day, and educating the patient about sleep-hygiene techniques should be implemented, along with nonpharmacologic interventions to help the patient achieve resolution. Clinical interventions that require sleep-inducing agents are often needed. Drugs that are used to decrease sleep latency (e.g., diphenhydramine and benzodiazepines) can also alter other phases of the sleep cycle, resulting in continued neurologic side effects of excessive daytime sleepiness and next-day drowsiness. Some of the newer agents (Z-drugs, or Z-hypnotics), such as Lunesta (eszopiclone), appear to have little effect on total sleep architecture and are recommended for short-term use for insomnia.[3,10]