Common and Serious Antibiotic Side Effects in Children

Antibiotics are some of the most prescribed medications in pediatrics, a branch of medicine that specializes in the care of those under the age of 18. However, they can come with side effects that range from unpleasant to life threatening.

This article explains the side effects of antibiotics that are prescribed to children. It will also suggest ways to avoid some of these side effects.

Young child being given medication.

Boonchai Wedmakawand / Getty Images

What Are Common Side Effects of Antibiotics in Children?

If your child develops a reaction while taking an antibiotic, or immediately after stopping one, be sure to tell your pediatrician. Common antibiotic side effects may include:

  • Diarrhea
  • Allergic reaction, which occurs when the immune system overreacts to something it views as dangerous
  • Drug-related rash
  • Yeast infection
  • Stained teeth
  • Fever

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Antibiotic rash on chest and arms of a man

Reproduced with permission from © DermNet New Zealand 2023.

Antibiotic-Associated Diarrhea

Getting diarrhea after taking antibiotics is a common side effect in children. Up to 30% of children will get diarrhea, either while they are still taking the antibiotic, or up to eight weeks after they have finished it.

Some antibiotics, such as cephalosporin, clindamycin, and certain types of penicillin, are more likely to cause diarrhea.

Allergic Reactions

Antibiotics can cause allergic reactions that may be immediate or delayed. An allergy-related rash may be raised or smooth, and is typically red. The rash may be itchy and can last for weeks. If your child develops a rash, reach out to your pediatrician right away.

Drug Reactions

Different types of rashes can show up in reaction to the antibiotic medication. Rashes may develop right away, or even weeks after your child has stopped their medication. Rashes related to a medication may be:

  • Red and peeling
  • Red or purple, raised bumps
  • Red and flat

Yeast Infections

Antibiotics kill both the good and bad bacteria in the body, which makes it easier for yeast to grow. This can lead to a yeast infection, which may impact the mouth, known as thrush, as well as the belly button, genitals, or nail beds.

Stained Teeth

Tetracycline, a type of antibiotic, is linked to tooth staining when given to children younger than 8 years old. However, research indicates that short-term use of doxycycline, a commonly used tetracycline, does not lead to tooth staining in children in this age range.

Another antibiotic, known as Amoxil (amoxicillin), may also lead to stained teeth. One study reported that toddlers age 20 to 24 months who took Amoxil had an increased risk of tooth staining later on.


Although often overlooked as a side effect, some antibiotics, such as cephalosporins and penicillin, have been associated with a drug-induced fever. The fever usually begins after a full week of taking the medication, but may go away shortly after your child finishes taking the antibiotic.

What Are Severe Side Effects of Antibiotics in Children?

Severe antibiotic side effects may include:

  • Anaphylaxis: Anaphylaxis is a life-threatening allergic reaction that includes symptoms like swelling, difficulty breathing, and reduced blood pressure.
  • Stevens-Johnson syndrome: This is a severe hypersensitivity reaction. Children may develop flu-like symptoms, painful sores, swelling of the face, and light sensitivity.
  • Toxic epidermal necrolysis (TEN): This is a severe form of Stevens-Johnson syndrome that may include symptoms such as excessive skin blistering and peeling.
  • Muscle pain: Children taking antibiotics may feel general muscle aches and pains.
  • Clostridioides difficile infections: This specific bacteria is common in children who have recently taken antibiotics and can cause diarrhea.
  • Red man syndrome: This reaction may occur in children who are on the antibiotic vancomycin. Symptoms may include itchy skin, a rash, fever, chest pain, and breathing difficulties.
  • Ototoxicity: Some antibiotics can lead to temporary or permanent hearing loss.
  • Pill esophagitis: A child's esophagus, the tube that connects the throat to the stomach, can become irritated by an antibiotic pill and lead to pain and difficulty swallowing.
  • Photosensitivity: Many antibiotics, like doxycycline, can make children more sensitive to the sun.
  • Drug-induced lupus: Children can develop symptoms of the autoimmune disorder systemic lupus erythematosus (SLE) while taking certain medications, such as the antibiotic minocycline.

How Do You Avoid Antibiotic Side Effects?

To avoid antibiotic side effects, only get a prescription for an antibiotic when it is needed. Taking antibiotics when they aren't needed can put your child at risk for side effects and encourages antibiotic resistance. Antibiotic resistance means the medications are unable to work effectively because the germs have evolved to not be impacted by the drug.

You may be able to avoid or reduce your child's chances of developing side effects by:

  • Taking a probiotic, which helps replenish good bacteria in the gut, and may prevent diarrhea
  • Protecting your child from the sun, by using sunscreen and avoiding peak sun hours, if the antibiotic increases the risk for sunburn
  • Taking the antibiotic as prescribed
  • Making sure your pediatrician knows about all other medications, including over-the-counter and natural remedies, that your child may be taking
  • Storing the antibiotic properly
  • Following directions on whether or not to take the antibiotic with food or on an empty stomach


While helpful, antibiotics can cause side effects that range from mild to severe. Common side effects include:

  • Diarrhea
  • Allergic reaction, such as an itchy rash
  • Drug-related rash, which may be raised or flat
  • Yeast infection
  • Stained teeth
  • Fever

Severe side effects may require immediate medical care. Examples of severe side effects include a life threatening allergic reaction, breathing difficulties, excessive skin peeling and blistering, as well as hearing loss.

To help manage the side effects of antibiotics, you can have your child take a probiotic, give your child the antibiotic as prescribed, and make sure your pediatrician knows about your child's medication history.

If you are worried about side effects or your child has had a reaction to their current antibiotic, be sure to speak with your pediatrician.

A Word From Verywell

If needed, antibiotics can be incredibly helpful for treating infections in children. If you are worried about your child experiencing potential side effects, be sure to speak with your pediatrician.

If your child does have a serious side effect that is associated with taking an antibiotic, seek emergency care immediately and also reach out to your pediatrician to let them know.

Frequently Asked Questions

  • How long do side effects from antibiotics last?

    For the most part, side effects from antibiotics will resolve when the treatment is finished. However, some side effects can take longer to clear up and others may not appear until after the medication is completed. If your child experiences troublesome side effects, call your pediatrician.

  • What antibiotics are most likely to cause a reaction in children?

    Penicillins and cephalosporins are most likely to cause an allergic reaction in children and adults. A rash is a common sign of an allergic reaction to antibiotics.

    Anaphylaxis is a less common, life-threatening allergic reaction with penicillin and cephalosporins antibiotics. If your child experiences any of the following symptoms of anaphylaxis, seek immediate medical attention: hives, difficulty breathing, wheezing, low blood pressure, and pale skin tone.

  • What antibiotics contain penicillin?

    Penicillin-based antibiotics are part of a larger family of medications known as beta-lactams. These include:

    • Amoxicillin
    • Ampicillin
    • Dicloxacillin
    • Flucloxacillin
    • Nafcillin
    • Oxacillin
    • Penicillin G
    • Penicillin V
    • Piperacillin
    • Ticarcillin

  • What antibiotics are cephalosporins?

    Cephalosporins that can cause an allergic reaction include:

    • Cefaclor
    • Cefadroxil
    • Cefazolin
    • Cefdinir
    • Cefotetan
    • Cefprozil
    • Cefuroxime
    • Keflex (cephalexin)
    • Maxipine (cefepime)

18 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. Chua KP, Volerman A, Conti RM. Prescription drug dispensing to us children during the COVID-19 pandemicPediatrics. 2021;148(2):e2021049972. doi:10.1542/peds.2021-049972

  2. Yan T, Goldman RD. Probiotics for antibiotic-associated diarrhea in childrenCan Fam Physician. 2020;66(1):37-39.

  3. Thong BY. Update on the management of antibiotic allergy. Allergy Asthma Immunol Res. 2010;2(2):77–86. doi:10.4168/aair.2010.2.2.77

  4. Johns Hopkins Medicine. Drug rashes.

  5. Children's Hospital of Philadelphia. Candidiasis (yeast infection) in children.

  6. Centers for Disease Control and Prevention. Research on doxycycline and tooth staining.

  7. Hong L, Levy SM, Warren JJ, Broffitt B. Amoxicillin use during early childhood and fluorosis of later developing tooth zonesJ Public Health Dent. 2011;71(3):229-235.

  8. Tabor PA. Drug-induced feverDrug Intelligence & Clinical Pharmacy. 1986;20(6):413-420. doi:10.1177/106002808602000601

  9. Norton AE, Konvinse K, Phillips EJ, Broyles AD. Antibiotic allergy in pediatricsPediatrics. 2018;141(5):e20172497. doi:10.1542/peds.2017-2497

  10. Sivagnanam S, Deleu D. Red man syndromeCrit Care. 2003;7(2):119-120. doi:10.1186/cc1871

  11. Merck Manuals Professional Version. Drug-induced ototoxicity.

  12. Bordea MA. Pill–induced erosive esophagitis in childrenClujul Medical. 2014;87(1):15-18. doi:10.15386/cjm.2014.8872.871.mab1

  13. U.S. Food and Drug Administration. The sun and your medicine.

  14. Van Steensel MA. Why minocycline can cause systemic lupus - a hypothesis and suggestions for therapeutic interventions based on it. Med Hypotheses. 2004;63(1):31-4. doi:10.1016/j.mehy.2003.12.040

  15. Cleveland Clinic. How to prevent diarrhea while you take antibiotics.

  16. Cleveland Clinic. Is medication making your skin sensitive to the sun?

  17. U.S. Food and Drug Administration. Combating antibiotic resistance.

  18. Medline Plus. Storing your medicines.

By Vincent Iannelli, MD
 Vincent Iannelli, MD, is a board-certified pediatrician and fellow of the American Academy of Pediatrics. Dr. Iannelli has cared for children for more than 20 years.