
Avoid driving or operating machinery for at least 4 hours after taking melatonin, or until the drowsy effects are no longer present.
Avoid using this medication with other prescription medications, over-the-counter drugs, or dietary supplements without asking your doctor, pharmacist or other healthcare provider.
Avoid alcohol while taking this medication.
Avoid coffee, tea, cola, energy drinks, or other products that contain caffeine, as it may counteract the effects of the melatonin.
What Happens if I Miss a Dose?
If you miss taking a dose there is no cause for concern, but melatonin may impair your thinking and reaction time. If you will be driving or doing any hazardous activity, skip your dose as melatonin can cause drowsiness.
Otherwise, use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine or double your dose to make up the missed medication.
Can You Overdose?
Melatonin is thought to be very safe in the short-term with a low risk for overdose. If you suspect an overdose or serious adverse reactions, seek emergency medical attention or call the Poison Help Line at 1-800-222-1222.
Is Melatonin Safe?
Melatonin is a relatively safe supplement when used in the short-term, and melatonin side effects are uncommon. Its safety in the long-term has not been determined in randomized, controlled studies. In general this medication appears to be relatively nontoxic, even at higher doses such as 3 to 5 mg once a day.
Some people can have side effects from melatonin that may include:
daytime drowsiness, dizziness, weakness, or confusion
vivid dreams, nightmares
feeling depressed, anxious, irritable
headache
loss of appetite, diarrhea, nausea, stomach pain
blood pressure changes
joint or back pain
elevated risk for seizures
Higher external doses(>1 mg to 10 mg) can worsen side effects like daytime drowsiness, impaired physical or mental ability, low body temperature, and elevated prolactin levels.
Related: Melatonin: Worth Losing Sleep Over?
