Antibiotics: Overdose vs. misuse

What are antibiotics?

Antibiotics are drugs that are used to treat bacterial infections. They act by either killing invading bacteria or by weakening them and making it easier for the body’s natural defenses to defeat the bacteria. Antibiotics can be taken orally, given by injection, or applied topically to the surface of the skin, eye, or other tissues.

Are antibiotics effective against viruses?

Antibiotics are not effective against viral infections, such as colds, flu, measles, or COVID-19. They are also not effective for treating fungal infections. Fortunately, there are other classes of drugs that can be used for some viral and fungal infections. When a drug is given, it always carries a risk-to-benefit ratio. The use of antibiotics for conditions other than bacterial infections can expose people to antibiotic side effects (risks) without any benefits. This can also contribute to the development of antibiotic resistance.

Can you overdose on antibiotics?

An overdose of an antibiotic is unlikely to result in serious symptoms. In 2023, US Poison Centers reported over 25,000 exposures to antibiotics; there was only 1 death. Often, no treatment is needed for an antibiotic overdose. However, an overdose of an antibiotic can cause stomach upset and upset the balance of the normal bacteria living in the gastrointestinal tract. This can lead to nausea, vomiting, and diarrhea that might be serious enough to need medical treatment. Milder cases can usually be managed at home with extra fluids.

Antibiotic resistance

Like all living things, bacteria are programmed to survive. Bacteria change or adapt over time; this is especially true of bacteria that are exposed to an antibiotic but not killed. Antibiotics that were effective a few decades ago are no longer effective because the bacteria they were intended to treat have become resistant to the antibiotics.

In some cases, the bacteria have changed their metabolic systems so that the antibiotics can no longer attack them. In other cases, bacteria have developed enzymes that destroy the antibiotics. According to one report, Staphylococcus aureus that has become resistant to methicillin (MRSA) now kills more Americans than emphysema, HIV/AIDS, Parkinson’s disease, and homicide combined. Worldwide, antibiotic-resistant tuberculosis has become a major public health problem.

Researchers are constantly working to develop new antibiotics, but the rate of new drug development is being outpaced by the rate of antibiotic resistance. Antibiotics should be used only in situations in which they are clearly needed. Antibiotic overuse is a major contributor to antibiotic resistance.

Using antibiotics wisely

There are simple things you can do to minimize the development of antibiotic resistance:

• Do not demand an antibiotic prescription just because you do not feel well. Most respiratory tract symptoms are self-limited and caused by viruses, but respiratory tract symptoms are a major reason for inappropriate antibiotic treatment.

• Do not take antibiotics without a prescription, and do not take someone else's antibiotic.

• Take antibiotics exactly as the label states: measure the correct dose, take (or give) each dose on time, and take the medicine for the full course that was prescribed even if you are feeling better.

• Do not take antibiotics left over from another illness.

If you have questions about your illness, or your child's illness, check with your healthcare provider. If you have questions about your prescription, contact your pharmacist.

If you think someone has taken too much of an antibiotic, use the webPOISONCONTROL^® online tool to get help, or call your poison center at 1-800-222-1222. Whether online or by phone, expert guidance is always free, confidential, and available 24 hours a day.