Will Jazz Pharmaceuticals (Nasdaq: JAZZ) investors be ecstatic or devastated when the Food and Drug Administration makes its final decision about the narcolepsy-turned-fibromyalgia drug now known as Rekinla? Perhaps a little of both.

In August, an advisory panel of outside experts voted 20-2 against approving Rekinla for fibromyalgia, so an FDA approval seems fairly unlikely. If fibromyalgia were a life-threatening disease without any treatment options, the agency might go against the panel's advice, but Pfizer's (NYSE: PFE) Lyrica, Eli Lilly's (NYSE: LLY) Cymbalta, and Savella from Forest Labs (NYSE: FRX) and Cypress Bioscience (Nasdaq: CYPB) are already approved to treat the condition. Some patients aren't helped by those drugs, but I doubt the FDA is going to see this as a medical necessity.

The saving grace for investors will likely come in what the agency says Jazz needs to do to get the drug approved. Here are some things to look for.

A name change. Jazz sells the same drug as a narcolepsy treatment under the brand name Xyrem. The company proposed selling the drug as Rekinla for fibromyalgia, but based on advisory panel comments, the FDA will likely want to stick with Xyrem to avoid potential double prescriptions for narcoleptics with fibromyalgia. The issue seems ridiculous to me. We don't worry about depressed smokers getting double doses by taking GlaxoSmithKline's (NYSE: GSK) antidepressant Wellbutrin and smoking cessation treatment Zyban, which are the same drug. But it's a minor thing to do if it helps the drug eventually gain approval.

More restrictive distribution. The active ingredient in Xyrem/Rekinla is related to the "date rape" drug GHB, which led to the FBI having a seat on the advisory panel. Because there are more potential prescriptions for fibromyalgia than narcolepsy, the agency wants to make sure the drug won't fall into the wrong hands. A more restrictive Risk Evaluation and Mitigation Strategies (REMS) will likely be required to make sure the right patients get the drug, which would typically trigger a six-month review after Jazz resubmits.

More clinical trials. The drug's efficacy doesn't seem to be in question, but some panel members seemed worried about the safety of the drug. If the FDA wants new trials, Jazz's hopes for increasing sales will be delayed significantly.

The first two seem like near-certainties to me, with the third being a bit of a wild card. I'd guess no new trials, but investors still have to factor it in as a possibility.

What do you think? Please take the Motley Poll below then scroll down to fill in the details in the comments box.

Pfizer is a Motley Fool Inside Value recommendation. The Fool owns shares of GlaxoSmithKline, which is a Motley Fool Global Gains pick. Try any of our Foolish newsletter services free for 30 days.

True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community.

Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. The Fool's disclosure policy loves binary events: Read it or not.