Like any medications you or your child receive, antibiotics can come with side effects. Most often, the benefit of these drugs far outweigh any risks, but adverse reactions do occur. What are some of the most common antibiotic side effects? What are some less common but serious side effects that may occur? And how can you reduce your risk when taking these medications?

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 percent 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 – Rashes as a drug reaction (rather than an allergic reaction) to an antibiotic may include itchy, maculopapular rashes or even delayed-onset urticarial (look like hives) rashes, but which is not an IgE-mediated allergic reaction and so won’t cause life-threatening anaphylactic reactions.

Yeast infections – Yeast infections may occur in different regions of the body and may include oral rashes (thrush) or genital rashes (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 the age of eight. Surprisingly, it is thought that even Amoxil may cause stained teeth. One study reported that kids who took Amoxil in the first three to six 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 intravenously (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. Allergic reactions may need to be treated with antihistamines or corticosteroids and yeast infections may need to be treated with topical antifungal medications.

Other Serious Antibiotic Side Effects
Antibiotics don’t just cause diarrhea and rashes. Just over 22 percent 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 the age of five years. That’s not surprising when you consider that some of those more serious side effects can include:

Anaphylaxis- Anaphylaxis is a life-threatening allergic reaction that includes multiple allergy symptoms, especially trouble breathing and/or reduced blood pressure.

Stevens-Johnsons syndrome – Stevens-Johnsons syndrome is 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, 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, red man syndrome includes flushing of the head and neck and sometimes, more seriously, life-threatening reactions.
Ototoxicity – Some antibiotics, especially aminoglycosides, like gentamicin, can 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. Of note is that these antibiotics are not used unless a child has a severe infection that is not likely to respond to other antibiotics.

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.