If you have liver disease, depression, or diabetes, you may not be able to take melatonin. Safety precautions also include avoiding the supplement if you are pregnant or breastfeeding, monitoring your blood sugar often, and watching out for possible drug interactions. Being aware of warnings and precautions with melatonin ahead of time can help minimize risks and ensure safe treatment.
Melatonin is a supplement often used to treat insomnia and other sleep disorders, although it is sometimes used for other purposes. You may not be able to take melatonin safely if you have:
- Seizures or epilepsy
- Liver disease, such as liver failure, cirrhosis, or hepatitis
- Any other allergies, including allergies to food, dyes, or preservatives.
Also, let your healthcare provider know if you are:
- Pregnant or thinking of becoming pregnant
You should also be sure to tell your healthcare provider about all other medicines you are taking, including prescription and non-prescription medicines, vitamins, and herbal supplements.
Warnings and precautions to be aware of concerning the safety of melatonin include the following:
- Melatonin can affect the level of sugar in the blood. If you have diabetes, check with your healthcare provider before taking the supplement. You may need to monitor your blood sugar more often, and your healthcare provider may need to adjust the dose of your diabetes medications.
- There have been reports that melatonin may worsen depression symptoms. If you have depression, check with your healthcare provider before taking the supplement.
- The liver helps to remove melatonin from your body. Therefore, if you have liver disease, your body may not handle the supplement as well as normal.
- Melatonin may worsen seizure disorders. However, there is some evidence that it may be helpful for seizures in some situations. If you have a seizure disorder, do not take melatonin without your healthcare provider's approval.
- Melatonin supplements can interact with some medications (see Melatonin Drug Interactions).
- It is not known if melatonin is safe for pregnant or breastfeeding women (see Melatonin and Pregnancy and Melatonin and Breastfeeding).
- If you decide to use supplements, what you see on the label may not reflect what is in the bottle. For example, some herbal supplements have been found to be contaminated with heavy metals or prescription drugs, and some have been found to contain much more or much less of the featured ingredient than the label states. Therefore, make sure the manufacturer of your melatonin product is trusted and reputable. It is a good sign if a manufacturer abides by the rules of Good Manufacturing Practices (GMP). It is also a good sign if a product has the United States Pharmacopoeia (USP) seal, which means that it has been independently tested and shown to contain the correct ingredients in the amounts listed on the label. Your pharmacist is a good resource for information about which manufacturers are most reputable.