Stopping medication for a week due to allergy testing - is it safe to take melatonin?

I went home for the holidays this year and during my time at home, I somehow developed a new, unknown allergy, my only guess is from an OTC medication. I have my testing appointment next week, which means I'm going to be very itchy and can't use my fan to help me fall asleep. As far as I know, this hasn't been caused by melatonin - can I take it to help me actually get some sleep for the next week? If this is better suited for a pharmacist, apologies, it was just on my mind. Thank you :)