It annoys me when people dismiss sleeping pills as categorically harmful. Yes, they can be used inappropriately and it’s important to be informed about their downsides. But the existence of downsides doesn’t necessarily mean the risks associated with using them outweigh the benefits.
The sleeping pill of choice for many Americans with insomnia can be purchased over the counter at drug and grocery stores. But a new study shows that many older adults who use OTC sleep aids know little about them and may be using them in ways that do more harm than good.
Older Americans Use Them and Like Them
Participants in the new study were adults in the United States aged 60 and older who were managing their sleep problems with nonprescription sleep aids. University of Pittsburgh investigators interviewed 116 by telephone and found that well over half were satisfied with their medication and felt it improved their sleep.
Asked about her satisfaction with one such drug, an interviewee replied that she was “pretty satisfied. It does help me fall asleep and stay asleep, and go back to sleep when I invariably get up once or twice a night.”
“There is a dramatic difference when I use it versus when I don’t,” another explained.
This jibes with the results of other, quantitative research. The prevalence of insomnia and other sleep problems among older adults is high and OTC sleep aids are widely available. About 17% of older adults in the United States turn for relief to antihistamine-containing sleep aids like Unisom and Simply Sleep.
How OTC Sleep Aids Work
Diphenhydramine and doxylamine are the active ingredients in antihistamine sleep aids. They block the action of histamine neurons, which are generally active when we’re awake and inactive when we’re asleep.
“Marked drowsiness may occur,” is the type of warning that usually appears on the label. This propensity to cause sedation is likely why, despite few controlled trials supporting their efficacy for insomnia, these drugs are seen as effective by many older adults. The trials that have been conducted suggest these antihistamine sleep aids may have more to offer sleep maintenance insomniacs than people who need help falling asleep at the beginning of the night.
Side Effects of OTC Sleep Aids
But like most prescription medications, OTC sleep aids are not intended for nightly or long-term use. Continuous use has been found to lead to the development of tolerance, tempting users to take more of the drug to get the same sedative effect. Yet in the Pittsburgh study, nearly half of the participants reported using OTC sleep meds daily or very often. Over half reported using them for more than a year.
Fewer than a quarter of the study participants had studied the label on their medication to find out about the recommended dosage or about warnings and possible side effects.
“I never really paid any attention to the directions,” an interviewee said. “I take a couple before I go to bed, about twenty minutes before I go to sleep, I go upstairs and go to bed. That’s it.”
Common side effects to be aware of are morning grogginess (our bodies process drugs more slowly as we age) and blurred vision, constipation, and trouble urinating (for more on this, see my post on OTC sleep aids and anticholinergic effects).
Possible drug-drug interactions is another factor to take into account, given that almost 40% of older Americans are taking five or more prescription medications. Studies have shown that diphenhydramine (the main ingredient in many OTC sleep aids, including Benadryl, Sominex, Nytol, ZzzQuil, and Simply Sleep) interferes with the body’s metabolizing of at least three commonly prescribed drugs:
- tamoxifen, an anti-estrogen drug used to treat breast cancer and lower breast cancer risk
- metoprolol (Lopressor), a beta blocker used to treat high blood pressure and heart problems
- venlafaxine (Effexor), a selective serotonin and norepinephrine reuptake inhibitor (SSNRI) used to treat depression
Reducing the effectiveness of a drug taken to manage a serious health condition isn’t something most of us would want to do. But information about all possible drug-drug interactions isn’t necessarily listed on the label of OTC sleep aids.
Americans seem to have the attitude that OTC meds are harmless—but that isn’t necessarily true. If you’re going to use an OTC sleeping pill, read the label for information about the proper dosage and potential side effects. Take concerns about possible drug-drug interactions to your doctor or pharmacist.