This is Dr. David
most likely it is fine for you to take melatonin.
melatonin has not been well studied with other conventional drugs.
you should let your doctor know you are taking melatonin for sleep.
there is no one better brand of melatonin.
you should see a sleep doctor and get a sleep study if you continue to have sleep problems.
I would use between 1-3mg of melatonin per night to see if that helps you sleep.
let me know if you have other questions.