How do doctors, pharmacists, nurses and patients learn about the potential side effects of medications? The basic source of all drug data is the official prescribing information approved by the Food and Drug Administration. You can find it online at DailyMed.

Most of the online databases rely on this information to let doctors and pharmacists know what to tell their patients. The only problem with this system is that it relies heavily on the original clinical trials conducted by the pharmaceutical manufacturer. Not all side effects come to light in such studies.

A classic example involves fluoroquinolone antibiotics such as ciprofloxacin (Cipro) and levofloxacin (Levaquin). This class of medications has been on the market for more than 30 years. It wasn’t until 2018, however, that the FDA warned the public that these antibiotics could increase the chance of tears in the aorta, a large blood vessel leading out of the heart. This complication is rare but potentially deadly.

Another example involves statin-type cholesterol-lowering drugs and elevated blood sugar. This was not reported in the original clinical trials. However, readers of this newspaper column began reporting trouble controlling their blood glucose while on these drugs. Eventually studies revealed that this was a true side effect of statins.

Once the FDA approves a medication, the drug company has relatively little incentive to continue looking for adverse reactions. It is usually left up to physicians, pharmacists and patients to voluntarily report problems that may be linked to a medicine.

Health professionals are busy people. They rarely have extra time to submit adverse event reports. Nobody pays them to do that.

The only people who have an incentive are the patients. This reader is concerned about the process:

“I have not met a soul who has not had uncomfortable reactions to medications. Many become depressed or lethargic. However, like me, they have been pressured to continue. I have a sister 14 months older than me. She has been on statins for years, and her complaints were addressed with antidepressants. Her cholesterol numbers are ideal. However, she rarely leaves her recliner chair and now she is diabetic.

“I myself have tried many blood pressure medications. None has been worth the muscle weakness and pain. I am very healthy and active. Beta blockers make it hard to exercise.

“I’ve also had rashes, runny nose, shortness of breath, wracking dry coughs and full body itching. My current physician says she hears this all the time, but if a patient has a heart attack, she miraculously becomes tolerant of the drugs.

“I always report any adverse reaction immediately with the assumption that my reactions are noted, reported and charted. I am not so sure. Who do they report to?

“Ireland has created a system for patients to directly report side effects. Do we have anything like this?”

Patients can report drug side effects directly to the FDA through MedWatch. This online reporting system is relatively easy to access for most people with an internet connection, although it may call for some information that is hard to find. That includes things like manufacturer, lot numbers, expiration dates and NDC (National Drug Code number). You can also report by phone: 800-FDA-1088.

Joe Graedon is a pharmacologist. Teresa Graedon holds a doctorate in medical anthropology and is a nutrition expert. Their syndicated radio show can be heard on public radio. In their column, Joe and Teresa Graedon answer letters from readers. Write to them in care of King Features, 628 Virginia Drive, Orlando, FL 32803, or email them via their website:

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