Brief Answer:
Could be an allergic reaction to melatonin.

Detailed Answer:
Hello,
Thanks for trusting Healthcaremagic!
I have gone through your query and I can understand your concerns.

As per your description it seems that your skin condition could be a simple allergic reaction to melatonin, even though allergic reaction is very uncommon with melatonin, some reported cases are there.
Melatonin does not cause any other skin related side effects.
You can stop the drug for few days and assess the severity of itching and rashes. If the symptoms still persist despite stopping the drug, it could be something else.

You can take over the counter anti allergic drugs like pheneramine and apply soothing lotions for symptomatic relief.
If symptoms persist, consult a dermatologist for detailed evaluation.
Kindly attach a picture along with the follow up question for better evaluation.
Thanks.

Dr.Shinas Hussain

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