Antibiotics: What Are They For? How Are They Used? What To Expect?


Antibiotics kill bacteria, not viruses and should be used only for diagnosed bacterial infections.

Viruses or Bacteria: What’s got you sick?1 



When should an antibiotic be taken?

  • Your health care provider will decide if antibiotics are necessary and which one to prescribe based on your symptoms and bacterial cultures.
  • Taking antibiotics unnecessarily can lead to antibiotic resistance. If you are sick and your bacteria is resistant to your prescribed antibiotic, complications such as hospitalization and death can occur.

How should I take my antibiotic?

  • Take your antibiotic as directed by your health care provider. Ask how to take your antibiotics (with food? without food?) and ask how to properly store your antibiotics. Some liquid medications may need refrigeration and some may need to be shaken well to ensure the right dose is taken.

How long should I take my antibiotic for?  

  • Follow the directions on the prescription and take antibiotics for the duration of treatment prescribed.
  • Antibiotics are prescribed for the amount of time it takes to kill the harmful bacteria.
  • Complete the entire antibiotic regimen and do not save antibiotics for later. Leftover antibiotics do not provide a complete dose.
  • Stopping the antibiotic regimen too early can allow the bacteria that have not yet been killed to restart the infection. Furthermore, resistant bacteria can occur when partial doses are taken.



Are antibiotics safe?

  • Antibiotics are generally safe when prescribed by a health care provider and taken as directed.
  • If you have experienced symptoms or allergies to antibiotics in the past, be sure to discuss your experience with your health care provider or pharmacist. If you’ve had allergic reactions to specific antibiotics in the past, you may experience similar reactions to drugs within the same class.

What are possible side effects of antibiotics?

  • Antibiotics can kill bacteria in body that are sensitive to them, which can include good bacteria. Disturbing the bacterial balance can lead to side effects such as stomach upset, diarrhea, vaginal infections, and other problems.2,3
  • Antibiotic-associated diarrhea is a common side effect of antibiotics. Frequent, watery bowel movements (diarrhea) can occur when antibiotics upset the balance of good and bad bacteria in your gastrointestinal tract. Sometimes, without enough “good” bacteria, the “bad” bacteria that are resistant to the antibiotic can grow out of control and produce toxins that can damage the bowel wall and trigger inflammation. Usually condition clears up shortly after the antibiotic is stopped, but occasionally, can lead to complications such as inflammation of the colon (colitis). Symptoms include loose stools and more-frequent bowel movements. Symptoms may begin about a week after starting antibiotics.
  • Contact your health care provider if you have any of the following symptoms:
    • Nausea
    • Fever
    • Poor appetite
    • Abdominal pain and cramping
    • Bloody stools
    • Mucus in your stool
    • Little or no urination, severe weakness, extreme dry mouth and/or thirst (signs of dehydration)
    • Persistent diarrhea without any signs of improvement after 2 days
  • Techniques to cope with your less serious diarrhea:
    • Drink more water and other liquids to replace the fluids lost due to the diarrhea and thereby avoid dehydration
    • Eat soft, bland foods (i.e. applesauce, bananas, rice)
    • Avoid high-fiber foods such as beans, nuts, and vegetables. You can slowly add high-fiber foods back into your diet once you feel your symptoms are improving.
    • Avoid irritating foods (i.e. spicy, fatty, or fried foods).
    • If your diarrhea continues after 48 hours of initial treatment, contact your health care provider

Can antidepressants affect my antibiotic medications?

  • Possibly. Always discuss your current drug regimen with your health care provider before they prescribe antibiotics so they may check for drug interactions that may interfere with the effectiveness of your medications.4

Is it OK to drink alcohol with my antibiotic?

  • Avoid alcohol while taking antibiotics because drinking can decrease your body’s ability to fight the infection and make your infection last longer.5

Important things women should know about antibiotics:

  • Vaginal yeast infections may occur (possible symptoms include itching, burning, pain during sex and vaginal discharge). Contact a physician if you think you have a yeast infection.
  • Some antibiotics may reduce the effect of birth control pills. An alternative form of birth control (i.e. condoms) may be needed while taking these medications. If you are having diarrhea and/or vomiting from taking any antibiotic or from your illness itself, a back-up form of birth control may also be required. For more information, click here.
  • If pregnant or nursing make sure your health care provider is aware as some antibiotics my cause harm to your baby.6

Antimicrobial Resistance7,8

  • Antibiotics kill bacteria that are sensitive to them, but resistant bacteria may be left to grow and multiply. Repeated and improper uses of antibiotics lead to drug-resistant bacteria. Antibiotics should not be used to treat viral infections. Viral infections include colds, flu, most coughs and bronchitis, and sore throats (except for those resulting from strep throat).
  • Antibiotic resistance is the ability of bacteria to resist the effects of an antibiotic. This allows the bacteria to survive and continue to multiply and cause more harm.

Consequences of Antibiotic Resistance

  • Drug-resistant organisms cause patients to suffer more (hospitalizations and even death) and pay more for treatment. 
  • Resistant bacteria can be transmitted to humans through the foods we eat and from contact with infected individuals.
  • Stop the spread of superbugs by adhering to antibiotic regimens as directed.

Ways to prevent antibiotic-resistant infections: