Consult your own doctor but been using this brand of Melatonin for 16 yrs to assist my sleep every night.
Other brands can be cheaper but not as high in quality and efficacy
Bought a years supply with the current 20% off at Iherb and additional 15% cash back Expired.
Paid cash back of $8.86 tracked immediately and comes with free shipping.
Some studies show it can be an effective treatment for covid as well. See FLCCC recommendations