What are the possible side effects of melatonin?
Although uncommon, allergic reactions to melatonin have been reported. Stop taking melatonin and seek emergency medical attention if you experience symptoms of a serious allergic reaction including difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives. Other less serious side effects have also been reported. Talk to your doctor or pharmacist if you experience
headache;
drowsiness; or
stomach upset.
Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.
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