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  5. Finding and Learning about Side Effects (adverse reactions)
  1. Information for Consumers and Patients | Drugs

Finding and Learning about Side Effects (adverse reactions)

From Minor to Life Threatening

Unwanted or Unexpected Drug Reactions

Drugs approved by the U.S. Food and Drug Administration (FDA) for sale in the United States must be safe and effective - which means that the benefits of the drug must be greater than the known risks. However, both prescription and over-the-counter (OTC) drugs have side effects. Side effects, also known as adverse reactions, are unwanted undesirable effects that are possibly related to a drug. Side effects can vary from minor problems like a runny nose to life-threatening events, such as a heart attack or liver damage.

Several things can affect who does and does not have a side effect when taking a drug – age; use of other drugs, vitamins, or dietary supplements; or other underlying diseases or conditions (for example, diseases that weaken the immune system or effect the function of the kidneys or liver).

Common side effects include upset stomach, dry mouth, and drowsiness. A side effect is considered serious if the result is: death; life-threatening; hospitalization; disability or permanent damage; or exposure prior to conception or during pregnancy caused birth defect.

Side effects can happen when you:

SideEffects

  • start taking a new drug or dietary supplement (for example, vitamins)
  • stop taking a drug that you’ve been on for a while, or
  • increase or decrease the dose (amount) of a drug that you take.

Reducing Your Risk

There are several ways to learn about side effects for your prescription drugs and to reduce your risk of experiencing a side effect.

  • Ask your health care professional about any possible side effects and what, if any steps should be taken to reduce the risk when you are prescribed a drug. For example, your health care professional may recommend taking the drug with food to lower the chance of getting nausea or to not take the drug with other drugs.
  • Ask your health care professional for information about the drug when you receive your prescription (FDA approved labeling for patients include Medication Guides and Patient Information). These documents will include possible common and serious side effects.
  • Read the pharmacy label and any stickers that may be attached to the prescription bottle or box. The label and stickers may have information on how to take the drug and possible side effects.

Prescription drug information on side effects is available on FDA’s Drugs@FDA database and FDA’s FDALabel database.

For over-the-counter drugs, read the Drug Facts Label.

When a Side Effect Occurs

Should you experience a side effect, you may be able to lessen or eliminate the effects. Work with your health care professional to see if adjusting the dosage or switching to a different medication will ease or eliminate the side effect. Other options, such as a lifestyle or dietary change, may be suggested by your health care professional.

Reporting Side Effects

When side effects do occur, you are encouraged to report them to FDA’s MedWatch, a program for reporting serious problems with human medical products including drugs.

MedWatch has a consumer reporting form, FDA 3500B. Written in plain language and designed to be consumer friendly, the form starts off with a page of some commonly asked questions and answers to help guide you in submitting the form, and then asks simple questions about the problem. In addition to formal reports, MedWatch has a toll free line (1-800-332-1088) to answer questions.

Be an active member of your health care team. By taking time to learn about the possible side effects of a drug and working with your health care provider and pharmacist, you will be better prepared to reduce your chance of experiencing a side effect or coping with any side effect that you may experience.

Where Can I Find Detailed Side Effect Information for a Drug?

FDA’s FDALabel database is used to perform customizable searches of thousands of drug labeling including searching for side effects for a drug. Please use these instructions to find side effect information about a particular drug.

  • Go to: https://nctr-crs.fda.gov/fdalabel/ui/search
  • If you are looking for a prescription drug for humans, click on “Human Rx”:
    • Go to the “Product Name(s)” search box and enter the entire or part of the drug name.
    • Consider looking for the trade name of the drug you are looking for and then click on “SPL Document” in that row.
    • Go the “6 ADVERSE REACTIONS” to find the side effects for the drug.
  • If you are looking for an over-the-counter drug for humans, click on “Human OTC”:
    • Go to the “Product Name(s)” search box and enter the entire or part of the drug name.
    • Consider looking for the trade name of the drug you are looking for and then click on “SPL Document” in that row.
    • Go to the “Warnings” to find the side effects for the drug.

 Resources with Side Effect Information

 
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