Antibiotic Side Effects

Identifying and Avoiding Antibiotic Side Effects

Saline followed by suctioning for an infant with a cold.
Nasal suctioning may help relieve symptoms of a cold. Marko Lazarevic/Getty Images

Antibiotics for Childhood Infections

Although antibiotic use has gone down in the past 10 to 20 years, they are still some of the most prescribed medications in pediatrics.

Contributing to the drop in antibiotic prescriptions include:

  • the addition of Prevnar to the childhood immunization schedule, which has directly led to fewer ear infections
  • more widespread use of the flu vaccine, which can lead to fewer kids with flu and secondary ear infections
  • more awareness of the risks antibiotic resistance, such as from MRSA
  • better antibiotic prescribing guidelines, including guidelines that advocate for watchful waiting for some kids with ear infections and sinus infections

Most importantly, though, there is a greater understanding of antibiotic side effects. Being aware of the side effects that antibiotics can cause will hopefully lead to even fewer unnecessary antibiotic prescriptions for colds and other viral infections so that antibiotics will work when we need them.

Common Antibiotic Side Effects

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

  • antibiotic-associated diarrhea - getting diarrhea when you take an antibiotic is much more common than many parents understand. It is thought that up to 25% of children will develop diarrhea, either while they are still taking the antibiotic, or up to a few weeks after they have finished it. While some antibiotics are thought to be more likely to cause diarrhea, including Augmentin and erythromycin, just about any antibiotic can cause your child to have diarrhea.
  • allergic reactions - antibiotics can commonly cause allergic reactions with hives. Unfortunately, many viral reactions can cause skin rashes that might be confused with an allergic reaction if they child is unnecessarily prescribed an antibiotic, causing problems when the child really needs the antibiotic at a later time.
  • drug reactions - which may include itchy, maculopapular rashes or even delayed-onset urticarial (look like hives) rashes, but which are not an IgE-mediated allergic reaction and so won't cause life-threatening, anaphylactic reactions.
  • yeast infections - can include thrush or Candidal vulvovaginitis.
  • stained teeth - classically, tetracycline derivatives caused tooth staining when given to young children during periods of enamel calcification, which is why these antibiotics (tetracycline, doxycycline, and minocycline) are not routinely used in children under age 8 years. Surprisingly, it is thought that even Amoxil may cause stained teeth. One study reported that kids who took Amoxil in the first 3 to 6 months of life had an increased risk of tooth staining later.
  • fever - although often overlooked as a side effect, some antibiotics have been associated with a drug-induced fever when they are given by IV.

Fortunately, most of these side effects are temporary, not life-threatening, and go away once your child stops the antibiotic he was taking.

Other Serious Antibiotic Side Effects

Antibiotics don't just cause diarrhea and rashes, though. Just over 22% of visits to the emergency room because of adverse reactions to prescription medications in 2011 were caused by antibiotics.

And one of the highest rates of emergency room visits involving medication side effects is in children under age 5 years. That's not surprising when you consider that some of those more serious side effects can include:

  • Anaphylaxis - a life-threatening allergic reaction that includes multiple allergy symptoms, especially trouble breathing and/or reduced blood pressure.
  • Stevens-Johnson syndrome - a life-threatening hypersensitivity reaction, children with Stevens-Johnson syndrome develop flu-like symptoms with painful ulcers or erosions in the mouth, nose, eyes, and genital mucosa, often with crusting.
  • Toxic epidermal necrolysis (TEN) - a severe form of Stevens-Johnson syndrome.
  • Musculoskeletal problems - Cipro (ciprofloxacin) and other fluoroquinolones are not generally used in children. They carry a risk of tendon rupture and possibly permanent nerve damage, and especially in children, Cipro can cause bone, joint, and tendon problems, including pain or swelling.
  • Clostridium difficile infections - C. diff is a bacteria that can cause diarrhea and other gastrointestinal symptoms, especially common in children who have recently been on antibiotics.
  • red man syndrome - a reaction that may occur in children who are getting IV vancomycin, who get flushing of their head and neck and sometimes, more serious, life-threatening reactions.
  • ototoxicity - some antibiotics, especially aminoglycosides, like gentamicin, can rarely cause cochlear or vestibular damage, leading to hearing loss. That is why it is important to monitor drug levels when children, especially newborns, are given this antibiotic.
  • pill esophagitis - a child's esophagus can be irritated by an antibiotic pill he is taking, especially if he has been prescribed doxycycline, which is rather large.
  • photosensitivity - many antibiotics, especially those used to treat acne, can make children more sensitive to the sun. This includes the antibiotics, tetracycline, minocycline, and doxycycline, for which extra care to reduce sun exposure should be taken while your teen is taking them.
  • drug-induced lupus - children can develop symptoms of systemic lupus erythematosus (SLE) while taking certain medications, especially high doses of minocycline for long periods of time.
  • benign intracranial hypertension - minocycline can sometimes cause benign intracranial hypertension or pseudotumor cerebri, in which children taking the medicine develop a chronic headache, nausea, and vomiting.

Unfortunately, since 2005, there has been a 69% increase in emergency room visits for antibiotic side effects. That makes it important to learn how to avoid them.

Avoiding Antibiotic Side Effects

Of course, the best way to avoid antibiotic side effects is to only get a prescription for an antibiotic when it is needed to treat a bacterial infection and take to take it as it is prescribed.

In addition to encouraging antibiotic resistance, when antibiotics can't kill bacteria anymore, taking antibiotics when they aren't needed can put your child at risk for side effects. After all, that prescription for Amoxil or Zithromax can't cause diarrhea or an allergic reaction if it was never written in the first place.

But when antibiotics are needed, like when your child has strep throat or pneumonia, you might be able to avoid or at least reduce your child's chance of developing side effects by:

  • taking a probiotic - several studies have shown that probiotics can prevent antibiotic-associated diarrhea in children.
  • drinking a full glass of water to prevent pill esophagitis if your child is taking doxycycline or other large pills or capsules.
  • be extra careful to protect your child from the sun if he is taking an antibiotic that might put him at increased risk for sunburn by using sunscreen, wear protective clothing, and limit exposure to the sun when it is at its strongest.
  • taking the antibiotic as prescribed, including finishing the whole prescription so that you don't have any left-over medicine.
  • avoiding interactions with other medications by 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, especially if it needs to be refrigerated.
  • follow directions on whether or not to take the antibiotic with food or on an empty stomach.

Most importantly, though, review the latest antibiotic prescribing guidelines so that you aren't looking for an antibiotic every time your child has a runny nose, sore throat, or minor ear infection.

What To Know About Antibiotic Side Effects

Although sometimes just a nuisance, side effects from antibiotics can be serious. Other things to know about antibiotic side effects include that:

  • Although not commonly used to treat young children, doxycycline is indicated for children with Ehrlichiosis and Rocky Mountain spotted fever, even if they are under age 8 years. In these cases, the risks of these serious tick-borne diseases are outweighed by the risks of taking the antibiotic.
  • In children, Cipro is indicated for the treatment of complicated urinary tract infections and pyelonephritis due to Escherichia coli. It is not a first choice drug in young children, though.
  • Omnicef (cefdinir) can sometimes cause a child's stool to have a reddish color because of an interaction with iron vitamins, baby formula with iron, or other iron-containing products.
  • Amoxil (amoxicillin) sometimes causes behavioral changes, including hyperactivity and agitation.
  • Children with a G6PD deficiency should not take certain antibiotics because of the risk of developing hemolytic anemia, including sulfonamides and nitrofurantoin.
  • Antibiotics treat life-threatening infections and have been described as miracle drugs and as one of the ten great public health achievements of the 20th Century. Don't let a worry of side effects keep you from taking antibiotics when you need them.

If your child does have a serious side effect that is associated with taking an antibiotic, you can report it to the FDA through their MedWatch online voluntary reporting form.


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Long: Principles and Practice of Pediatric Infectious Diseases, 4th ed.

Substance Abuse and Mental Health Services Administration. 2011: National Estimates of Drug-Related Emergency Department Visits. Accessed October 2013.

The Role of Probiotics in the Prevention and Treatment of Antibiotic-Associated Diarrhea and Clostridium Difficile Colitis. Gastroenterology Clinics of North America, Volume 41, Issue 4, December 2012, Pages 763-779.

Wright J. Complications of antibiotic therapy. - Med Clin North Am - 01-JUL-2013; 97(4): 667-79

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