Over the counter sleep aids
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Prevalence and Patterns of Over-the-Counter Sleep Aid Use
Over-the-counter (OTC) sleep aids are widely used, with estimates suggesting that about 18% of the population have tried them, and 41% of users continue for more than a year . Usage is especially common among older adults, with over 44% of those aged 65 and above reporting frequent use . Patterns of use vary, with some individuals using these aids intermittently, while others become chronic users, particularly those with more severe insomnia or depressive symptoms . Younger adults, especially female students, also report high rates of use, often without consulting healthcare professionals .
Common Ingredients in OTC Sleep Aids: Diphenhydramine, Doxylamine, Melatonin, and Herbal Supplements
The most common OTC sleep aids contain antihistamines such as diphenhydramine (Benadryl) and doxylamine (Unisom), as well as supplements like melatonin and herbal products such as valerian 1234+2 MORE. In some regions, herbal mixtures and melatonin are prevalent, with products like suanzaorentang being popular in Hong Kong .
Efficacy and Safety of OTC Sleep Aids
Antihistamines (Diphenhydramine and Doxylamine)
Clinical evidence supporting the effectiveness of diphenhydramine and doxylamine for sleep is limited. While some studies show a modest increase in sedation and a decrease in the number of awakenings, overall benefits are not robust, especially for long-term use 256. These medications are associated with side effects such as dizziness, next-day drowsiness, and cognitive impairment, which are particularly concerning in older adults 4789. The Beers Criteria recommend that people aged 65 and older avoid these medications due to the risk of falls and cognitive decline, yet more than half of older adults using OTC sleep aids take products containing these ingredients 78.
Melatonin
Melatonin, especially in prolonged-release formulations, has shown more consistent benefits for improving sleep onset and quality, particularly in older adults, and is generally well-tolerated with minimal adverse effects 245. However, there is limited research on its long-term safety, and some concerns exist about potential effects on fertility and cellular toxicity, though these are not well-studied in humans .
Herbal Supplements (Valerian, Kava, and Others)
Herbal supplements like valerian and kava are commonly found in OTC sleep aids, but evidence for their effectiveness is weak and inconsistent 236. Safety data are also inadequate, and more rigorous studies are needed to clarify their risk-benefit profile .
Risks, Misuse, and the Need for Professional Guidance
OTC sleep aids are often used without medical supervision, leading to risks such as incorrect dosing, long-term use, and dangerous interactions with other medications 147. Many users are unaware of the potential side effects and safety concerns, especially older adults who are at higher risk for adverse outcomes 78. Chronic use and self-medicating behaviors are common, and high-frequency users are less likely to be good sleepers and more likely to have other health issues .
Conclusion
OTC sleep aids are widely used for insomnia and sleep disturbances, but their effectiveness and safety—especially for long-term use—are not well established. Antihistamines like diphenhydramine and doxylamine carry significant risks for older adults, while melatonin appears safer and more effective, particularly in older populations. Herbal supplements lack strong evidence for efficacy or safety. Increased awareness, better research, and professional guidance are needed to ensure safe and appropriate use of OTC sleep aids, especially among vulnerable groups such as the elderly.
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