What are the side effects of melatonin?
Sep 26, 2024
Source: Cainiu Health
Dr. Liu Wenmin
Introduction
Under normal circumstances, melatonin is a hormone secreted by the pineal gland that primarily regulates the body's sleep-wake cycle, also known as the circadian rhythm. In clinical practice, melatonin is commonly used as an adjunctive treatment for insomnia, jet lag, and related conditions. Potential side effects include dependence, altered mental status, endocrine disturbances, gastrointestinal discomfort, and disruption of sleep patterns.
Under normal circumstances, melatonin is a hormone secreted by the pineal gland that primarily regulates the human sleep-wake cycle, also known as the circadian rhythm. In clinical practice, melatonin is commonly used as an adjunctive treatment for insomnia, jet lag, and similar conditions. Potential side effects include dependency, altered mental state, endocrine disruption, gastrointestinal discomfort, and disturbances in sleep rhythms. A detailed analysis is as follows:
1. Dependency
Melatonin exerts its effects by binding to receptors on cell surfaces. With prolonged use, the body may develop adaptive changes, requiring continuously increasing doses to achieve the same effect, thus leading to dependency. Long-term melatonin use may alter the body's natural melatonin secretion patterns. Upon discontinuation, the body may fail to quickly return to its original sleep-regulating state, resulting in reduced sleep quality.
2. Altered Mental State
Melatonin has certain regulatory effects on the nervous system. However, long-term use may lead to neurological dysfunction, causing symptoms such as mood swings, irritability, and fatigue.
3. Endocrine Disruption
As a hormone, melatonin secretion is regulated by multiple factors. Prolonged use of exogenous melatonin may interfere with the secretion and metabolism of other hormones in the body, disrupting hormonal balance. This can lead to menstrual irregularities and decreased sexual function. Women may experience irregular menstrual cycles, while men may suffer from reduced libido.
4. Gastrointestinal Discomfort
Melatonin may directly irritate the gastrointestinal mucosa, causing adverse reactions such as nausea, vomiting, abdominal pain, diarrhea, or constipation.
5. Disruption of Sleep Rhythm
Melatonin secretion follows a distinct circadian rhythm—suppressed during the day and active at night. Long-term use of melatonin may disrupt this natural rhythm, leading to circadian misalignment. Paradoxically, this may worsen sleep rhythm disorders and potentially contribute to neurasthenia.
To minimize the side effects of melatonin, it is recommended to consult a physician or pharmacist before use to determine whether it is appropriate for individual circumstances. Additionally, users should follow medical advice or product instructions regarding dosage and administration, avoiding excessive or prolonged use. When using melatonin to treat insomnia, it is advisable to maintain moderate dietary control, engage in regular physical activity, and increase daytime exercise, all of which can promote better nighttime rest and reduce reliance on melatonin for sleep.
