DEAR DR. ROACH: Could you offer any general advice on how patients should weigh the risks versus benefits when they are prescribed a drug that lists many potentially serious side effects? I once had a specialist suggest that I do a trial of a drug for a noncardiac issue, but my cardiologist cautioned me not to chance it because both my heart status and age put me in a higher risk category for the specific drug.

So, I declined to use it, figuring the risk was too great. The drug in question was also very new to the market. This leads me to ask: Do recently approved drugs pose more of a risk simply because they haven’t been around long enough and used by enough patients to adequately know what their adverse effects will prove to be over time? — K.B.

ANSWER: It is true that we understand the safety profile of established drugs better than we understand the safety of brand-new drugs. Although any drug needs to be studied extensively before it can be approved by the Food and Drug Administration, it is also true that there are many instances where harms became known only after many people have taken the drugs for years. (Fen-phen and Vioxx are two examples.)

I generally avoid prescribing brand-new drugs until they have a bit of a track record, as long as there are tried-and-true alternatives. But I do have colleagues who are quick to use the newest one. There are certainly times when a new medicine is such an improvement over what exists that it is taken up right away by the medical field in general. There are also drugs that have been used for many years in other countries with a good safety record.

Asking your specialist is another good idea. Your cardiologist knows you, and although they might not know every new drug, they can look up the potential harms from the studies that got the drug approved and apply them to you.

DEAR DR. ROACH: I am a healthy 87-year-old man. Two months ago, I had an accident that injured my shoulder, resulting in full-thickness and full-width tears of my rotator cuff tendons. I’ve been doing physical therapy daily for eight weeks and have achieved some range of motion and reduced pain. But I believe the physical therapy will only bring limited results.

I have heard about stem cell therapy and platelet-rich plasma for such injuries.

What is your opinion on these methods? Do the cells come from the patient’s body, or can younger cells be used? I know insurance doesn’t cover this, but I’d be willing to pay for it if it would bring healing. I’d sure like to get back to playing golf again. — J.J.B.

ANSWER: If eight weeks of physical therapy haven’t returned you to the level of function that you want, it’s time to see a surgeon. In my opinion, the studies on platelet-rich plasma and stem cells, while promising, do not yet support their use. (A person’s own body is used to get stem cells, usually from bone marrow or fat tissue.)

I know that they are being used now, and I see testimonials to their effectiveness, but I haven’t found the kinds of quality trials that consistently show benefit.

I am quite conservative and want to see clear evidence before recommending that a patient spend their hard-earned money on an unproven technique.

EDITOR’S NOTE: Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu or send mail to 628 Virginia Dr., Orlando, FL 32803.