Go ahead and have that Double-Double at In-N-Out Burger. But before you go, make sure you get a prescription for Abbott Labs' (NYSE:ABT) new cholesterol drug, TriLipix, with a side of statins.

The Food and Drug Administration gave TriLipix the thumbs-up yesterday, approving it for use by itself or with statins like Pfizer's (NYSE:PFE) Lipitor, AstraZeneca's (NYSE:AZN) Crestor, or generic versions of Merck's (NYSE:MRK) Zocor. Heck, Bristol-Myers Squibb's (NYSE:BMY) Pravachol, or the generic from Teva Pharmaceutical (NASDAQ:TEVA), might even qualify.

TriLipix doesn't lower "bad" LDL cholesterol quite as well on its own as when it's used with statins. However, it does lower blood fats called triglycerides, on which statins have little effect, in addition to raising "good" HDL cholesterol -- thus the "tri" in the name.

The drug is a follow-up to Abbott's TriCor, which brought in $886 million in the first nine months of the year -- that's a whole lot of hamburgers. Abbott's goal now is to get as many patients as possible to switch to TriLipix before TriCor goes off-patent in 2011. The biggest selling point seems to be that TriLipix is approved for use with statins, while TriCor isn't. But because doctors are free to prescribe approved drugs in combination, TriLipix sales are still likely to take a hit when TriCor goes off-patent in a few years.

Abbott has another trick up its sleeve as well. It's also developing a pill with AstraZeneca that combines TriLipix and Crestor. The two hope to seek marketing approval next year. The combo pill seems like a win for everyone. It will be more convenient for patients, and it could result in lower copayments even after TriCor goes generic. AstraZeneca's Crestor would get preference over other statins, thanks to its convenient combination with TriLipix, while Abbott would gain access to a base of existing high-cholesterol patients whose current drugs might need an added boost.

TriLipix won't be a home run for Abbott, but it doesn't really need to be. As long as it can keep the inning alive by getting patients to switch, the development should pay for itself.

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Fool contributor Brian Orelli, Ph.D., prefers his Double-Double made animal style. He doesn't own shares of any company mentioned in this article. In an emergency, the Fool's disclosure policy makes a good napkin.