You may have heard about two expensive new cholesterol-­lowering drugs: alirocumab (Praluent) and evolocumab (Repatha). Both are injectables recently approved by the Food and Drug Administration and are expected to cost $1,100 to $1,200 per month. That compares with about $48 per year for commonly prescribed cholesterol-­lowering statin drugs such as generic lovastatin, pravastatin, and simvastatin.

Those new drugs, called PCSK9 inhibitors, can dramatically reduce LDL (bad) cholesterol—even in people who’ve been unable to sufficiently lower their LDL with the maximum dose of a statin. But it’s not yet known whether that translates into a reduced risk of heart attack, stroke, or premature death—and that question won’t be answered until ongoing studies have been completed.

In addition, because the medications are so new, their long-term safety is unknown. The most common side effects seen so far include pain at the injection site and symptoms similar to those of a cold or the flu. Serious allergic reactions have occurred as well.

So should you ask your doctor about adding one of the new cholesterol drugs to your regimen? For now, the drugs are approved only for people with a genetic condition that causes extremely high LDL levels, and those who have already had a heart attack or stroke and can’t get their LDL levels down despite high-dose statins and a serious effort to make lifestyle changes.

If you fall into one of those categories, ask your doctor whether you should wait until more is known about the drugs, or whether they make sense for you to try now. Other people should definitely wait.

Be aware that if you do start either of the new cholesterol drugs now, your health insurance may cover the costs only if you take it for one of the FDA’s approved uses. And it’s still unclear whether Medicare will cover the drugs.

Both Sanofi (the maker of Praluent) and Amgen (which makes Repatha) told us that they have programs that can lower out-of-pocket costs for some people. But there are eligibility restrictions—you can’t be on Medicare or Medicaid, for example. And depending on the program, you may have to give the pharmaceutical company information such as your medical history and doctor’s name.

For more on cholesterol medications, see our free Best Buy Drugs report on statins.

Editor's Note: This article also appeared in the February 2016 issue of Consumer Reports On Health.

This article and related materials are made possible by a grant from the state Attorney General Consumer and Prescriber Education Grant Program, which is funded by the multistate settlement of consumer-fraud claims regarding the marketing of the prescription drug Neurontin (gabapentin).