Healthier LivingGeneral Health Tips
Apr 25, 2023
7 Minute Read

Adverse reaction versus side effect: What’s the difference?

When you pick up your prescriptions at the pharmacy, you probably notice the list of side effects included on the label or the printout you receive from your pharmacist. If that long list of potential side effects scares you, we get it.

But think of it this way: It’s evidence of the thorough clinical approval process undertaken by the Food and Drug Administration (FDA). These warnings demonstrate an ethic of full disclosure and transparency, and that’s a good thing for patients.

To learn more about this part of understanding your medication, we talked to Sahar Swidan, Pharm.D., R.Ph. She’s an adjunct associate professor at George Washington University School of Medicine and Health Sciences in Washington, D.C., and an adjunct clinical associate professor of pharmacy at Wayne State University in Detroit.

Swidan talked about side effects, adverse reactions, and how you can keep yourself as safe as possible when you take prescription medications.

What’s the difference between an adverse reaction and a side effect?

“Adverse drug reactions are generally unknown or unintended responses to a medication,” says Swidan. “Side effects have been reported before.”

When medications come to market, they’re accompanied by a list of potential side effects that have been detected in clinical trials. Swidan says they usually include the incidence of these potential side effects. “After a drug is marketed, post-marketing surveillance takes place,” she says. “We continue to monitor for new adverse drug reactions that haven’t been picked up in prior studies.”

When to talk to your doctor and pharmacist

The ideal time to talk to your provider is when the medication is prescribed. It’s your doctor’s responsibility to start this conversation. “Your doctor should discuss these potential adverse reactions with you: what can happen and when to reach out for help for the more serious ones,” says Swidan. “Your clinicians and pharmacists should be teaching you about proper use of the medication, potential side effects, and proper next steps to manage it.”

When your doctor tells you about a new medication, ask questions. Find out if you should expect any side effects or if an adverse reaction is possible.

Also, Swidan says, “Always speak to your pharmacists. They are part of your patient care team and can really help you understand your medications as related to proper use and potential side effects.”

Learn more about Medicare Advantage member pharmacy benefits.

How can I learn more about possible side effects of my medication?

No problem. You can find it on the FDA’s Drugs@FDA database.

At the top of the document, you’ll find this phrase: “What is the most important information I should know about XYZ drug?” This is usually followed by a list of the primary side effects. It will also include directions on what to do.

What to do when you have a reaction to medication

Don’t ignore it—touch base with your provider. But what will happen next depends on a few factors. First, you need to think about how serious the reaction is.

“As an example, we know that bleeding is a potential side effect of blood thinners,” says Swidan. And if you experience bleeding, you need to notify your care team or go to the emergency room right away.

On the other hand, some side effects, such as nausea, are less alarming. Nausea is a common side effect of many medications. Sometimes it is just a matter of giving your body time to adjust, or making adjustments to how you take the medications, like taking them with a meal. If it continues to be a problem, like progressing from nausea to vomiting, you should report it to your provider right away to discuss options.

Why do medications list so many side effects?

Every adverse drug reaction and side effect encountered during clinical drug trials has to be reported to the FDA. As a result, the list can get long. “If the patient sneezes, we have to report that to the FDA during clinical drug trials,” says Swidan.

For that reason, “it’s important to look at the percentage of incidence. Some are more common, and the more serious or potentially scary adverse reactions or side effects in general are rare,” she says.

“But they can still occur. That’s why it is critical to inform patients of all potential side effects regardless of how rare they are so patients can self-monitor,” advises Swidan.

Bottom line: It’s up to you to look out for yourself throughout your treatment. Talk to your doctor and pharmacist about side effects before you start taking a medication. That way, you know what to expect.

Additional source:
Drug approval process: U.S. Food and Drug Administration
“The FDA’s Drug Review Process: Ensuring Drugs Are Safe and Effective.” Food and Drug

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Blue Cross and Blue Shield of Kansas City’s Blue Medicare Advantage includes both HMO and PPO plans with Medicare contracts. Enrollment in Blue Medicare Advantage depends on contract renewal.

Blue Cross and Blue Shield of Kansas City is an independent licensee of the Blue Cross and Blue Shield Association. The HMO products are offered by Blue-Advantage Plus of Kansas City, Inc. and the PPO products are offered by Missouri Valley Life and Health Insurance Company, both independent licensees of the Blue Cross and Blue Shield Association, and wholly-owned subsidiaries of Blue Cross and Blue Shield of Kansas City.

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