Panic Attacks Caused By Prescription Sleep Aids?
Ambien Pharmacology and Indications
Ambien (zolpidem tartrate) is classified as a nonbenzodiazepine, hypnotic drug. The indicated use is for the short-term treatment (8-12 weeks) of insomnia. Ambien selectively binds to the GABA receptor in the brain and is effective in reducing the amount of time it takes to fall asleep and extending sleep time, but not in maintaining sleep throughout the night. For this reason, Ambien controlled-release (CR) has been developed to provide a steady release of the drug throughout the night, in an effort to support sleep maintenance.
Anxiety Risk with Ambien Treatment
A recent national, double-blind, placebo-controlled study of the effectiveness and problems associated with Ambien CR was completed recently (1). Patients enrolled in the study were diagnosed as having chronic primary insomnia based on DSM-IV criteria, and were otherwise physically healthy and free of psychiatric problems. Interestingly, 65.2% of the study participants receiving Ambien ER and 52.7% of the placebo group completed the study, suggesting only 12.5% of insomnia patients found Ambien to be more effective than placebo in improving their sleep quality.
Of the group receiving Ambien CR, 63.2% experienced an adverse event. When compared to the placebo group there was an 11.9% increase in adverse events due to the drug. Even though the most common complaint was headache, there was no difference between the two groups. The next most common complaint was anxiety, with a significant difference between the Ambien CR (6.3%) and placebo (2.6%) groups. This suggests that Ambien treatment results in 3.7% of insomnia patients experiencing one or more mild to moderate episodes of an anxiety disorder, which would include panic attacks. Other reported adverse events included sleepiness (3.7%), dizziness (2.8%), fatigue (1.3%), attention deficits (2.6%), nausea (1.1%), and nasal infections (2.4%).
Ambien Dependency
The published research literature contains several reports of patients who developed a dependency on Ambien, sometimes taking 16 to 200 times the recommended daily dose (3). The current theory is that at these dosage levels, Ambien acts in a manner similar to benzodiazepines (3). Benzodiazepines are prescribed for short-term treatment of insomnia and anxiety disorders, are susceptible to dependency, and sudden withdrawal can cause anxiety disorders, depression, insomnia, tremors, and headaches (4). Anyone who has developed a dependence on Ambien would therefore be at risk for experiencing these withdrawal symptoms.
Alternative Insomnia Treatments
People who experience significant adverse reactions to Ambien are typically advised to stop taking it. There are a number of alternative sleep aids available, including over the counter medications like 400 mg of valerian root, diphenhydramine (Benadryl), and doxylamine (Unisom), and prescription hypnotics similar to Ambien and benzodiazepines (2).
1. Krystal, A. D. et al., 2008. Long-term efficacy and safety of zolpidem extended-release 12.5 mg, administered 3 to 7 nights per week for 24 weeks, in patients with chronic primary insomnia: A 6-month, randomized, double-blind, placebo-controlled, parallel-group, multicenter study. Sleep, 31, p.79-90.
2. Ringdahl, E. N., Pereira, S. L., and Delzell, J. E., 2004. Treatment of primary insomnia. Journal of the American Board of Family Practitioners, 17, 212-219.
3. Cubula, W. J., Landowski, J., and Wlchowlcz, H. M., 2007. Zolpidem abuse, dependence and withdrawal syndrome: sex as susceptibility factor for adverse effects. British Journal of Clinical Pharmacology, 65, p.444-445.
4. Khong, E., Sim, M. G., Hulse, G., 2004. Benzodiazepine dependence. Australian Family Physician, 33, p.923-926.
