Why You Shouldn't Take Antibiotics That Aren't Prescribed to You

Most of us have been there - you've been sick for a few days then you wake up with serious ear pain, a severe sore throat or sinus pressure so intense you feel like your head is going to explode. You know you have an ear infection, strep throat, sinus infection, etc., and you don't want to take time out of your day to go to the healthcare provider. Your friend has some leftover antibiotics so you'll just take them. Problem solved.

An assortment of colored pills on a white surface
Rafe Swan / Cultura / Getty Images

Not so fast. 

Have you ever heard that you shouldn't take medications that aren't prescribed for you? You might think it only applies to painkillers or some other type of medication but there are very important reasons why it includes antibiotics as well. 

You May Not Need Antibiotics 

First, the illness you have or the pain you are feeling may not be caused by a bacteria at all. Many ear infections, sore throats and even lingering coughs like bronchitis are caused by viruses. Antibiotics don't kill viruses. Taking another person's antibiotics may not help you and taking antibiotics when you don't need them leads to antibiotic resistance.

Only your healthcare provider can determine if your illness is caused by a bacteria. Depending on your symptoms and certain tests, if your healthcare provider feels strongly that antibiotics are necessary, then you should take them. But just because your best friend had similar symptoms and was given antibiotics doesn't mean you do too. And it certainly doesn't mean you should take hers. 

You Might Need Different Antibiotics

Not all antibiotics are the same. They don't all kill the same germs. Certain medications are best used for certain infections. If the specific bacteria causing the infection has been identified, your healthcare provider can figure out which antibiotic is best to treat it. Even if they don't know the exact bacteria, healthcare providers are trained to know how to figure out which antibiotics are most appropriate for specific infections.

The antibiotic that your friend has may not be the one you need to treat the infection you have. Even if it's the same type, you may need a different dose or to take it more or less frequently than the person it was prescribed for. 

You Could Be Endangering Your Own Health

If you take any other medications, herbal supplements or have any chronic health conditions, you should not take additional medications (especially prescriptions - antibiotics or others) without discussing it with your healthcare provider. They could interact with other medications you are taking, causing dangerous reactions or side effects.

They may not be safe if you have certain medical conditions. Don't put yourself at risk by taking antibiotics that weren't prescribed for you by a healthcare provider that knows your medical history. 

There Isn't Enough Left

Even if your friend had the exact antibiotic you need, you have a real bacterial infection that could be treated by that antibiotic and you have no other concerns about interactions or chronic medical conditions, you still shouldn't take your friend's leftover antibiotics because there won't be enough. 

If someone stops taking their antibiotics once they feel better instead of taking the entire amount that was prescribed, they may have some leftover. But that isn't enough to adequately treat an infection. Taking less than the full amount prescribed means that you may not completely treat the infection, increasing the chances that the bacteria develop resistance to that antibiotic. 

As you can see, there are many reasons not to take another person's antibiotics. If you think you have an illness that requires antibiotic treatment, take the time to see a healthcare provider so it can be treated fully and correctly without contributing to the very real threat of antibiotic resistance.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Be antibiotics aware: smart use, best care.

  2. Centers for Disease Control and Prevention. Antibiotic Resistant Threats in the United States.

  3. Cleveland Clinic. 4 important facts you need to know about antibiotics.

  4. U.S. Food and Drug Administration. Drug interactions: what you should know.

  5. World Health Organization. Does stopping a course of antibiotics early lead to antibiotic resistance?

Additional Reading

By Kristina Duda, RN
Kristina Duda, BSN, RN, CPN, has been working in healthcare since 2002. She specializes in pediatrics and disease and infection prevention.