The short answer
Do all prescription drugs have side effects?
Yes. Every medication has the potential to cause side effects — prescription drugs, over-the-counter remedies, vitamins and herbal supplements alike.
Why medications cause side effects
- They reach the whole body. Drugs work by interacting with chemicals and processes in your body, and those same chemicals often control more than one process.
- The helpful action can also do harm. The mechanism that treats your condition can trigger an unwanted reaction at the same time — a blood thinner that prevents clots also makes bruising more likely.
- Everyone’s biology is different. Age, genetics, other health conditions and everything else you take all influence how your body reacts.
Key facts about side effects
- Not everyone gets them. A medicine that can cause a side effect will not necessarily cause it in you.
- Severity varies widely. Reactions range from mild annoyances, like a dry mouth or drowsiness, to serious and life-threatening complications.
- Approval is a balance, not a guarantee. The U.S. Food and Drug Administration approves a drug when its overall benefits are judged to outweigh its known risks.
Look it up
Check any prescription drug in the PDR
The Prescribers’ Digital Reference (PDR) lets you look up prescription medications, dosages, warnings, drug interactions and adverse reactions online.
Its content matches the FDA-approved package inserts supplied by each drug’s manufacturer, and a mobile version, mobilePDR, is available for healthcare professionals.
Speak up
How to report an injury or adverse reaction
Anyone can file a report — patients, parents, caregivers and healthcare providers. Reports are how regulators spot problems no clinical trial caught.
Drug injuries & adverse reactions
Report adverse events, medication errors or product quality problems to the FDA MedWatch program — online, by mail or by fax.
Call the FDA at 1-800-FDA-1088, or contact the drug manufacturer’s medical information department.
Vaccine injuries
Report through the Vaccine Adverse Event Reporting System (VAERS) — submit online or download a writable PDF.
Need help? Call 1-800-822-7967 or email info@VAERS.org. For compensation after a serious vaccine injury, see the National Vaccine Injury Compensation Program.
Is it an emergency? If you or someone near you is having a severe reaction — trouble breathing, swelling of the face or throat, chest pain, fainting — call 911 right away. Reporting can wait.
Sources
- Better Health Channel — Medicines and side effects
- healthdirect — Medicine and side effects
- British Heart Foundation — Medication side effects
- U.S. FDA — Finding and learning about side effects
- Parkview Health — Medication side effects: how bad is too bad?
- Healthify NZ — Side effects of medicines
- CDC — VAERS access and use
- VAERS — Frequently asked questions
This page is for education only and is not medical advice. Never stop or change a prescribed medicine without talking to your prescriber or pharmacist first. See our disclaimer.
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