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Symptoms and Signs of Antibiotics (Side Effects, List, Types)

Doctor's Notes on Antibiotics Side Effects and Types

Antibiotics frequently prescribed medications that are used to cure disease by killing or injuring bacteria. The first antibiotic was penicillin and today over 100 different antibiotics are used to cure everything from minor to life-threatening infections. The main classes of antibiotics include penicillins, cephalosporins, macrolides, fluoroquinolones, sulfonamides, tetracyclines, and aminoglycosides. Antibiotics will only treat bacterial infections. They are useless against viral infections such as the common cold and fungal infections such as ringworm.

Common side effects of antibiotics may include soft stools or diarrhea or mild stomach upset. Tell your doctor if you have more serious side effects while taking antibiotics including vomiting, severe watery diarrhea and abdominal cramps, allergic reaction (shortness of breath, hives, itching, swelling of lips, face, or tongue, or fainting), rash, vaginal itching or discharge, or white patches on the tongue.

Medical Author: John P. Cunha, DO, FACOEP
Medically Reviewed on 3/21/2019

Antibiotics Side Effects and Types Symptoms

Some people are allergic to certain types of antibiotics, most commonly penicillin. If you have a question about a potential allergy, ask your doctor or pharmacist before taking the medicine.

Allergic reactions commonly have the following symptoms:

  • Shortness of breath
  • Rash
  • Hives
  • Itching
  • Swelling of the lips, face, or tongue
  • Fainting

Bacterial Infections 101 Types, Symptoms, and Treatments Slideshow

Bacterial Infections 101 Types, Symptoms, and Treatments Slideshow

Bacteria are microscopic, single-cell organisms that live almost everywhere. Bacteria live in every climate and location on earth. Some are airborne while others live in water or soil. Bacteria live on and inside plants, animals, and people. The word "bacteria" has a negative connotation, but bacteria actually perform many vital functions for organisms and in the environment. For example, plants need bacteria in the soil in order to grow.

The vast majority of bacteria are harmless to people and some strains are even beneficial. In the human gastrointestinal tract, good bacteria aid in digestion and produce vitamins. They also help with immunity, making the body less hospitable to bad bacteria and other harmful pathogens. When considering all the strains of bacteria that exist, relatively few are capable of making people sick.


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.