While statins have worked wonders for many people, they’ve also made a lot of money for drug companies. And as new statins come out, those companies are going to work hard to recruit you to their side. So how can you tell which statin is right for you and what’s just marketing hype?

First, realize that all statins lower cholesterol by the same mechanism, so they all lower LDL and triglycerides and boost HDL cholesterol a small amount, though they differ in degree in all of these things. The members of the statin family also share similar major side effects. Second, note their differences:

• Ingredients. Each brand-name statin differs from the others in that it has a unique chemical structure. The statin pills also contain distinctive inactive ingredients used to hold it together, preserve it, and get it into the bloodstream.

These variances can cause the body to handle each drug differently. If you have a side effect on one brand of statin, it does not guarantee that you will have the same side effect on a different brand.

• Potency. Some statins are more potent than others, meaning that the same dose lowers cholesterol by different amounts. A 20 mg tablet of Pravachol, for example, lowers LDL by 24 percent on average, while a 20 mg tablet of Lipitor lowers it by 46 percent.

But potency doesn’t matter as much as the medication’s efficacy—the maximum amount a statin can lower LDL at its highest FDA-approved dose. Lipitor used to be strongest, but now it has to share this honor with Crestor. Remember, though, that you don’t necessarily need to pick the strongest statin if a “weaker” one gets you to your target LDL level.

• Proof of benefits. Four of the statins—Mevacor, Pravachol, Zocor, and Lipitor—have been tested the most in large clinical trials showing that the drugs prevented heart attacks and deaths from heart disease. There is less proof that Lescol and Crestor do the same thing, but most experts believe that the benefits of statins are shared across the six drugs.

• Cost. You can pay anywhere between $35 and $120 for a month’s worth of statin tablets. Which statin will be least expensive for you can depend on your health insurance. Because all the statins seem to be beneficial, it’s reasonable to pick the cheapest one that gets you to your target LDL level.

The first statin approved, lovastatin, is now available generically, and simvastatin and pravastatin will soon follow, so these will all likely be cheaper alternatives to brand-name-only statins.

• Side effects. Statins’ unwanted side effects fall into four main camps: liver changes, muscle pain, interactions with drugs and food, and everything else. The first two, as noted earlier, are nearly the same for all the statins. The others aren’t necessarily.

That’s because the liver uses one set of reactions to break down Mevacor, Zocor, and Lipitor; a different set for Lescol and Crestor; and yet another for Pravachol. Drugs or foods that block these reactions can boost statin levels in the blood, while drugs that rev up the process can lower statin levels.

Grapefruit juice, for example, increases blood levels of Mevacor, Zocor, and Lipitor but doesn’t usually affect the others. But it takes a lot of grapefruit juice to make this difference matter, so it may be an important factor for only a few individuals who drink unusually large amounts of it.

People taking statins have reported constipation, upset stomach, dizziness, trouble sleeping, rashes, and even hair loss. Because these could be reactions to a specific statin, changing to a different one may help. If not, you may need to switch to another type of cholesterol-lowering drug, such as niacin, colesevelam (WelChol), or ezetimibe (Zetia).

The choice of which statin to take—assuming it is appropriate to take one—has traditionally been made by your doctor. However, you are entitled to ask why he or she chose one statin over the others. There may be an equally effective and less expensive alternative, which most doctors are happy to prescribe if they are asked to consider it.