Other, less common melatonin side effects might include short-lasting feelings of depression, mild tremor, mild anxiety, abdominal cramps, irritability, reduced alertness, confusion or disorientation, and abnormally low blood pressure (hypotension).

Can melatonin make you jittery?

Over-the-counter supplements are not regulated and there isn't a standard dose of melatonin in each one. And, some people, especially older adults, experience the opposite effect and feel anxious and jittery after taking it.

Why do I feel weird after taking melatonin?

Stomach problems Melatonin also causes stomach discomfort in some people. This may include cramps, nausea, and diarrhea. Dizziness Some people who take melatonin also report mild dizziness, lightheadedness, or vertigo. Irritability Too much melatonin can also affect mood.