Excessive melatonin effects
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Common Side Effects of Excessive Melatonin Use
Excessive melatonin intake is generally associated with mild and short-lived side effects. The most frequently reported symptoms include drowsiness, dizziness, fatigue, headache, confusion, nightmares, low blood pressure (hypotension), rapid heart rate (tachycardia), and mild hypothermia. These effects are usually manageable and resolve with supportive care and monitoring of vital signs Higueras2022Schrire2021Foley2019.
Serious Adverse Events and Safety Profile
Despite the widespread use of melatonin, even at higher doses (≥10 mg), serious adverse events are rare. Most studies report that melatonin does not significantly increase the risk of severe adverse events or withdrawals due to side effects. However, there is a slight increase in minor adverse events such as drowsiness, headache, and dizziness. Overall, melatonin is considered to have a favorable safety profile, but more comprehensive safety reporting is needed in future studies, especially for long-term use Schrire2021Foley2019.
Endocrine and Cardiovascular Effects
Some studies have noted that excessive melatonin can affect endocrine and cardiovascular systems. These effects may include changes in reproductive hormone levels, glucose metabolism, blood pressure, and heart rate. The likelihood and severity of these effects can depend on the dose, timing of administration, and interactions with other medications, particularly antihypertensive drugs .
Management of Melatonin Overdose
In cases of melatonin overdose, supportive care is the main treatment. Monitoring and controlling vital signs are essential, and most patients recover without complications. Severe toxicity is uncommon, and melatonin is considered one of the least toxic medications available .
Conclusion
Excessive melatonin use is generally safe, with most side effects being mild and temporary, such as drowsiness, dizziness, and headache. Serious adverse events are rare, but some endocrine and cardiovascular effects may occur, especially at higher doses or with certain drug interactions. Supportive care is usually sufficient for managing overdose, and melatonin remains a low-toxicity supplement when used appropriately Higueras2022Schrire2021Foley2019.
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