Melatonin supplements are synthetic versions of the hormone melatonin that can be taken in pill form as a dietary supplement. They are commonly used as a sleep aid to help people with insomnia or jet lag fall asleep faster and stay asleep longer. Melatonin supplements also help people with certain sleep disorders, such as delayed sleep phase disorder, shift work sleep disorder, and insomnia caused by certain medications. Melatonin supplements are considered safe for most adults to use short term. Still, it’s essential to consult with a healthcare professional before taking them, especially if you have certain health conditions or are taking other medications.