Have you noticed the side effects listed for one of those new drugs being advertised on TV? It may seem as if one of those marvelous medicines might be a good solution for your problem, but the long list of possible problems could be a bit daunting. How likely is it that you would experience some of them?

Unfortunately, that question is shockingly hard to answer. For example, you might be intrigued by an ad for a drug to treat bipolar disorder, such as Vraylar (cariprazine). In the ad, this drug helps a person calm the chaos in her life.

Then, there is a long list of side effects, starting with the warning that it isn’t appropriate for elderly people with dementia. Fine, that’s not you.

What about “fever, stiff muscles or confusion, which may be life-threatening?” “Uncontrolled muscle movements which may be permanent?” “High blood sugar, which can lead to coma or death?” We are told that certain side effects are common: “difficulty moving, tremors, slow or uncontrolled body movements, restlessness and feeling like you need to move, sleepiness, nausea, vomiting and indigestion.”

If your doctor suggested that this drug could be appropriate for you, you might have a challenging time weighing the pros and cons. Physicians can learn about the benefits and risks from data generated by randomized controlled trials.

You too can find this, because the trials that led to Food and Drug Administration approval are summarized at DailyMed.nlm.nih.gov. Most drug entries at that site list “adverse reactions” (aka side effects) under heading No. 6.

Here is where it can get puzzling. If you check Vraylar, you’ll find the symptoms listed in the ad. There are others that didn’t make it into the commercial. What you see on television has no numbers to suggest how common a side effect might be.

For example, you might want to know about headaches (listed in DailyMed as affecting 13% of patients). Some people also find constipation (11%) challenging, though it is not mentioned in the commercial either.

Even when the prescribing information lists the percentages of people experiencing drug side effects, the data may be confusing.

For example, semaglutide is available for diabetes control or weight loss. In both cases, the manufacturer offers patients either a pill or an injection. All contain the same compound.

You would imagine, therefore, that the side effects of these drugs (sold under the brand names Ozempic, Rybelsus and Wegovy) would be relatively similar. In actuality, they differ more than you’d expect. Ozempic causes nausea in about 20% of patients, and so does Rybelsus. But Wegovy, which is the exact same drug, is associated with 44% nausea for the injectable form and 46% for the tablet.

Diarrhea is another difficult side effect. Approximately 9% of those on Ozempic suffered from this problem compared to 10% on Rybelsus. But in the trial for the pill Wegovy, 17.6% of those on the drug reported diarrhea. Also, 30% of people injecting Wegovy experienced diarrhea.

All these numbers are important only if you are thinking of starting one of these meds. They provide an illustration of how difficult it can be to find out which side effects to expect from the prescription your doctor is writing.

In their column, Joe and Teresa Graedon answer letters from readers. Write to them in care of King Features, 300 W. 57th Street, 41st Floor, New York, NY 10019, or email them via their website: www.PeoplesPharmacy.com. Their newest book is “Top Screwups Doctors Make and How to Avoid Them.”