Natrol is a company that makes a large number of supplements, not drugs. You mention GNC, which is a place everyone should avoid. They have no concern whatsoever about your well-being and have been caught selling things that are falsely labeled so many times it's amazing they haven't been closed down. So did you really mean Natrol, a company, or did you mean a particular supplement the company makes, or is there a drug I don't know about called Natrol or maybe you have the wrong name? Okay, I saw your link and googled it, this is a supplement, not a drug, and you don't need a doctor to prescribe it. I wouldn't personally take it, but try it, see what happens. Natrol is a long-standing supplement company, so it's not some direct marketed or internet scam, but this supplement combines things that should be taken separately. You also won't get the proper dosage of anything necessarily taking it. There are two forms, one for sleep and one for anxiety, but you don't mention which one you're taking. The main ingredient is 5-HTP, which is an amino acid metabolite of tryptophan. Along with B6, vitamin C and other co-factors this is what the body uses to manufacture serotonin. If your body thinks you need more of it, it will use this to make more of it. If it doesn't, it won't. But dosing with 5-HTP is done similarly to using antidepressants, which means you start with a small dose and work up to the dose that studies show works. You can't do that taking something like this that has a bunch of different things in it. It also works best if taken apart from food. Again, I don't think it'll hurt to try it, but it isn't the best approach. The best approach if you know nothing about natural medicine, and your doctor probably knows nothing about natural medicine, is to see someone who does specialize in it, such as a naturopath or doctor who practices integrated medicine. I'm guessing a doctor who does that wouldn't use this particular product, but again, it's a reliable company so I don't think it'll hurt any to try. If nobody found it effective they wouldn't be able to sell it. But from now on, buy your supplements from a quality health food store, not a GNC. It's safer that way. Good luck.
I totally agree with the above regarding GNC.