Waking up with a foggy mind and lethargic body is an all too common experience with some sleep aids, particularly hormonal options like melatonin. “‘Grogginess’ is sometimes reported after melatonin use, along with headache, dizziness, upset stomach, and even mood alterations such as temporarily feeling down or feeling more anxious,” Ellen Wermter, FNP-BC, a family nurse practitioner, previously told mindbodygreen.

This can happen if there is so much melatonin in your supplement that the hormone is still lingering in your system when you wake up. The melatonin is sending the signal that it’s nighttime as you’re going about your morning routine, which can lead to that dazed and confused feeling. Supplements with abnormally high levels of melatonin are not uncommon, as recent testing has shown.

Your sleep supplement should help you fall asleep and wake up feeling good, so if you’re having this issue, consider it a red flag.