Catching ZZZs: A Summary of the Most Common Herbal Medications Taken for Insomnia

Melatonin

Melatonin is a hormone that is naturally produced in the brain and plays a vital role in regulating sleep-wake cycles. It is available in supplement form over the counter and is commonly used as a sleep aid for people who have trouble falling or staying asleep. Melatonin supplements are available in various forms, such as tablets, capsules, gummies, chewables, sublingual, and liquid formulations. Scientifically known as N-acetyl-5-methoxytryptamine, melatonin is an indoleamine hormone secreted endogenously at night and responsible for mediating the circadian rhythm. ² It is synthesized in the pineal gland; synthesis starts from tryptophan, converted to 5-hydroxytryptophan, then to serotonin, then to N-acetylserotonin, and finally to melatonin. As far as sleep is concerned, melatonin is a sleep regulator and helps signal darkness in humans. Melatonin levels usually increase in the evening as darkness falls and remain elevated throughout the night before dropping off as daylight approaches. ² Regarding dosing, a study that observed 20 healthy males found that when taking doses even as little as 1.0 mg, their sleep-onset latency and how long it took to fall asleep decreased from 17 to 6 minutes. ³ In another study looking at young adults, oral administration of 5 mg of melatonin caused a significant increase in the transition from wakefulness to sleepiness and the duration of rapid eye movement (REM) sleep. In a meta-analysis, doses of greater or less than 3 mg had an increased effect on sleep quality. ⁴ Compared to other sleep aids, melatonin is well-tolerated and has a low potential for dependency. Potential side effects users may experience are nausea, dizziness, headache, and more severe effects of the increased risk for seizure. ⁵

Melatonin is primarily metabolized in the liver by the CYP2C19 and CYP1A family, possibly involving CYP2C9 and CYP2C19. ⁶ This leads to recommending caution when patients are taking antihypertensives, anticoagulants, anticonvulsants, and antidiabetic medication. Patients should notify their primary care physician when using melatonin. Pregnant patients should also tread on the side of caution when considering this sleep aid, as there is insufficient data to support its use.

Valerian

Valerian, a perennial plant with fragrant flowers, is native to Europe and Asia and also grows in North America. ⁷ The plant has a pungent smell and has been used as a sedative by Greeks and Romans since ancient times. ⁸ It is available in various dosage forms, such as capsules, tablets, liquid extracts, and teas. ⁷ For the treatment of insomnia, a recommended dosage of 300–600 mg (equivalent to 2–3 g of dried valerian root) is suggested, whereas tinctures require a dose range of 2.5–5 mL. Valerian root (Valeriana officinalis L.), the most extensively researched natural substance, modulates GABAa and produces sedative, anxiolytic, and antidepressant effects. ⁹ In vivo studies have suggested that the plant and its constituents produce sedative, anxiolytic, and antidepressant effects. In vitro studies have highlighted the potential of valerian and its components to modulate various neurotransmitter systems, including γ-aminobutyric acid, adenosine, and serotonin systems. ⁷ The use of ethanolic valerian extract has been associated with adverse effects such as headache, gastrointestinal upset, mental dullness, and depression. In contrast, the use of aqueous extracts has been linked with dizziness and nausea.

Lavender

Lavender is a popular plant known for its fragrant smell and calming properties. The plant has been widely used for centuries as a natural remedy in pharmacy, phytotherapy, and aromatherapy to alleviate various central nervous system disorders, including but not limited to anxiety, stress, and sleep disorders. ¹⁰ Lavender may have an effect on sleep due to its ability to increase melatonin levels. A study was done on 67 older adult patients, which included intervention on mediating sleep disturbances with aromatherapy. This resulted in a significant increase in blood melatonin levels in the total population. Both older adult men and women can benefit equally from aromatherapy with lavender essential oil, as it has been shown to increase blood melatonin levels. ¹¹ Lavender is available as an oral, inhalation, and topical formulation. The oil can be used topically by applying it directly to the affected area or by massaging it into the skin. It can also be added to bath water for a relaxing experience. When used via inhalation, lavender oil is commonly diluted to a 1% to 5% formulation and can be added to a diffuser or placed onto a cotton ball, gauze pad, or the inside of an oxygen face mask. Immediate-release soft gelatin capsules of 80 or 160 mg doses are also available for use. Lavender is generally well-tolerated but does come with possible side effects that include breath odor, constipation, diarrhea, headache, nausea, and allergic contact dermatitis (when used topically). While there hasn’t been much research on the safety of using lavender oil during pregnancy, a study has shown that inhaling essential oils during labor did not appear to negatively impact the infant. ¹² Additionally, there have been reports of lavender associated with prepubertal gynecomastia.

Additional Over the Counter and Herbal Medications People Take for Sleep

Other supplements have also been used as sleep aids for plentiful years. Although the data is insufficient, there is an association between improved sleep and these supplements, including but not limited to kava, magnesium, and cannabidiol (CBD).

Kava is another commonly discussed plant that individuals use to help with sleep hygiene. While it is generally well tolerated, there has been a high amount of case reports reporting hepatotoxicity. Many countries, including Germany, Switzerland, France, Canada, and the United Kingdom, removed kava-containing products after re-evaluating the association between kava and hepatotoxicity. Meanwhile, in the USA, the Center for Food Safety and Applied Nutrition (CFSAN) and the FDA addressed this issue by issuing a Consumer Advisory titled “Kava-containing dietary supplements may be associated with severe liver injury” to the public. ¹³

Magnesium, an element more commonly known for supporting bone structure, has seen increased discussion for use as a sleep aid. Multiple formulations are available, and specific studies have specified using magnesium oxide and magnesium citrate tablets. Studies suggest that taking up to 1 g of elemental magnesium per day in divided doses of twice or thrice per day could positively affect sleep parameters. Furthermore, it was observed that doses greater than 5 mg have been linked to renal and cardiac side effects. Since oral magnesium is easily accessible and inexpensive, the data is insufficient to discourage the recommendation of oral magnesium supplementation as a treatment for insomnia symptoms in older adults. ¹⁴

Cannabidiol (CBD) could be a promising solution for those who struggle with sleep issues. According to an Australian study, CBD has been shown to not only increase the total sleep time but also reduce the time it takes to fall asleep. ¹⁵ Cannabidiol is available orally as well as topically. It can be consumed in daily doses of 200 mg or less for up to 13 weeks or in single doses of 300–600 mg. Taking cannabidiol with food or beverages, such as whole milk, can enhance its absorption, whereas alcohol can also aid in its absorption. Consuming oil-based cannabidiol products with fatty foods can significantly increase its absorption and reduce the time taken to achieve maximum plasma concentrations. ¹⁶ Topical formulations of cannabidiol, such as oils, lotions, and gels, are commonly used in combination with other ingredients. However, the effect of sublingual cannabidiol alone for insomnia remains unclear since it has only been evaluated in combination with other ingredients.

Conclusion

Sleep is a vital part of health and the lack of sleep leads to various consequences and complications. Insomnia often causes people to seek out solutions for restful sleep, not just because of the long-term effects of lack of sleep, but also because it can be an acutely frustrating problem to experience that can greatly impact the day-to-day quality of life. While the data shows that certain herbal and over the counter medications may be helpful for insomnia, more research is needed to determine their efficacy and safety. It is vital that a thorough medication history is taken to ensure the patient is not taking any medications that may be causing the insomnia as well as to check for the presence of any potential drug-drug or drug-disease interactions. Many of these herbal medications do not have sufficient data to see the effects on fetal development during pregnancy or effect on breastfeeding. The clinical data discussed highlights some of the information available to date; however, there are both small and large studies that continue to evaluate the role these medications may play in insomnia.

Generally, if these medications are used, it is recommended that they are only taken for a short duration of time. Additionally, if herbal medications are chosen, it is important to consider that they are not approved by the Federal Drug Administration and therefore do not have the same stringent rules to follow. If recommending a person take an herbal medication, recommend choosing a product that has a seal of approval—this does not mean that the product is safe and effective per FDA standards; however, it does mean that the product complies with good manufacturing practices. A thorough assessment and lifestyle interventions are foundational to include in the management of insomnia, while the use of certain herbal medications may be considered on an individual basis. ¹⁷