Common Antibiotics Prescribed to Children: What Parents Should Know

• Penicillin, amoxicillin, and Augmentin are among the most frequently prescribed antibiotics for bacterial infections in children, but they have no effect on viral infections.
• About 10% of children receive a penicillin allergy label, yet approximately 95% of these diagnoses are incorrect; true allergic reactions are uncommon and include symptoms such as rash, swelling, low blood pressure, and wheezing.
• Overuse and misuse of antibiotics accelerates the development of antibiotic resistance and can harm the gut microbiome, with lasting negative health consequences.
• Healthcare providers minimize antibiotic resistance by selecting the narrowest-spectrum agent appropriate for the infection and, when possible, adjusting treatment based on laboratory culture results to target only the specific pathogenic bacteria.

As the school year approaches, children face inevitable exposure to numerous infectious pathogens—viruses like colds and influenza, as well as bacterial illnesses such as strep throat and pneumonia. Parents often wonder which infections warrant antibiotic treatment and what to anticipate when their child receives one of these medications. Medical experts provide guidance on the antibiotics most commonly given to pediatric patients, their intended uses, and typical outcomes.

7 common children's antibiotics

Viruses do not respond to antibiotics; however, when a child develops a bacterial infection, a pediatrician will likely prescribe one of several standard options. According to Michael Grosso, MD, chairman of pediatrics at Huntington Hospital at Northwell Health in Huntington, New York, these medications are available in both liquid formulations and tablets suited to different ages and preferences.

1. Penicillin

Penicillin, the first antibiotic ever discovered, remains effective for numerous bacterial infections ranging from strep throat and ear infections to serious bloodstream infections and skin infections. Mild side effects such as rash, diarrhea, nausea, vomiting, or abdominal pain occur in some children; rarely, a black, hairy tongue may develop. Approximately 10% of children receive a penicillin allergy diagnosis, though research indicates that roughly 95% of these cases represent misdiagnosis. Genuine allergic reactions manifest with symptoms including facial or airway swelling, reduced blood pressure, wheezing or throat tightness, and urticarial rash with itching.

2. Amoxicillin

Amoxicillin, a derivative penicillin, stands among the most commonly prescribed pediatric antibiotics. Its oral absorption is superior to penicillin, producing higher concentrations in blood and urine. According to Dr. Grosso, "It is the preferred first-line medication for most children with middle ear infections (also known as acute otitis media), acute sinusitis, sore throat due to Group A streptococci (so-called strep throat), some infections of the urinary tract, the rash phase of Lyme disease, and a variety of other infections." Nausea, vomiting, diarrhea, headache, and taste disturbances represent common side effects.

3. Augmentin

Augmentin combines amoxicillin with clavulanic acid, a component that enhances amoxicillin's effectiveness against certain bacteria that would otherwise resist treatment. Clinicians use it for select middle ear infections, sinus infections, urinary tract infections, and skin infections, as well as following animal bites. Potential side effects include diarrhea, stomach upset, vomiting, and mild skin rash.

4. Zithromax

Zithromax (azithromycin) serves as a second-line option for ear, sinus, and throat infections and is also employed as a first-line agent for penicillin-allergic patients, per Dr. Grosso. Its prolonged activity allows once-daily dosing, typically for five days, making it convenient for parents to administer, though it is somewhat less potent for bacterial infections compared to other options above. Dr. Grosso notes that "azithromycin is the preferred antibiotic for certain germs called atypical bacteria, which can cause pneumonia in children and adults." Nausea, vomiting, diarrhea, abdominal pain, and headache rank among the common side effects.

5. Biaxin

Biaxin (clarithromycin) treats pediatric bacterial infections including pneumonia, bronchitis, and infections of the ear, skin, throat, and sinuses. The medication is recognized for its poor palatability. Potential side effects include diarrhea, nausea, vomiting, taste changes, flatulence, and headache.

6. Keflex and Omnicef

Keflex (cephalexin) and Omnicef (cefdinir) belong to the cephalosporin antibiotic family, which are structurally related to but distinct from penicillins. Most individuals with penicillin allergy can tolerate these medications safely, though not universally. Dr. Grosso explains that "cephalexin is often prescribed for urinary tract infections or skin infections, while cefdinir treats most infections that respond to Augmentin. Cefdinir can usually be taken just once a day." Cefdinir may produce diarrhea, nausea, vomiting, abdominal pain, rash, genital itching, and headache. Cephalexin carries additional potential effects including heartburn, fatigue, agitation, dizziness, confusion, and rectal itching.

7. Sulfonamides

Sulfonamides represent one of the oldest antibiotic classes, in use since the 1930s and proven effective across a spectrum of infections. Bactrim (sulfamethoxazole/trimethoprim), the most frequently prescribed sulfonamide combination, addresses middle ear, sinus, urinary tract, and skin infections. According to Dr. Grosso, approximately 3–8% of people develop sulfonamide allergy, most commonly presenting as rash. Standard side effects include dizziness, headache, diarrhea, nausea, vomiting, appetite loss, and nervousness.

Additional considerations for pediatric antibiotic use

While many other antibiotics benefit pediatric patients, the seven above represent the most widely dispensed options, according to Dr. Grosso. Some antibiotics, including Vancocin (vancomycin) and Flagyl (metronidazole), are typically given intravenously in hospitalized children. Others are formulated topically—as creams, ointments, or eye/ear drops. "When appropriate, topical antibiotics are usually preferred because of their better safety profile," Dr. Grosso says.

In pediatric practice, all antibiotics undergo weight-based dosing calculations (mg/kg) divided into 1–3 daily doses depending on the specific drug, explains Rebecca Fisk, MD, a pediatrician at Lenox Hill Hospital at Northwell Health in New York. Dr. Fisk emphasizes that "when a pediatrician prescribes an antibiotic for a specific illness, it is important that the dosing be adhered to and completed as directed." Parents should notify their pediatrician if questions arise or side effects develop, and should not discontinue treatment without medical guidance. Medication must be given directly to the child rather than concealed in beverages or food, which may result in incomplete administration.

Antibiotics that should be avoided in children

Fluoroquinolones such as Levaquin (levofloxacin) and tetracyclines like doxycycline are generally contraindicated in pediatric patients. Tetracyclines carry risk of permanent tooth discoloration, while quinolones were observed to cause cartilage damage in animal studies, prompting restricted use pending further research, according to Dr. Fisk.

When antibiotics should not be used

Antibiotics are ineffective against viral pathogens and therefore cannot treat colds, rhinorrhea (including when discharge is discolored), most sore throats, influenza, or other viral illnesses, Dr. Fisk notes. Children with known antibiotic allergies must avoid the specific medication in question.

Antibiotic resistance develops when repeated or excessive antibiotic exposure allows bacteria to evolve protective mechanisms against the drug. As Dr. Fisk explains, frequent antibiotic use enables bacteria to develop defenses, while Dr. Grosso adds that widespread resistance spreads through communities as resistant germs circulate among people, progressively reducing medication effectiveness.

The bacteria residing in the intestines and respiratory tract compose a delicate ecological system with significant health implications. Excessive antibiotic use can severely disrupt this gut microbiome balance, producing substantial adverse health effects. For this reason, antibiotics should only be used when specifically indicated by a healthcare provider.

Avoiding antibiotic resistance

Healthcare providers reduce antibiotic resistance risk by selecting the narrowest-spectrum antibiotic available to treat the specific infection, Dr. Grosso explains. "Under the best of circumstances, we send a culture to the lab (say from the throat, or the urine) to identify the culprit specifically." Broad-spectrum agents are reserved for serious infections requiring rapid intervention. Once laboratory results identify the bacterial pathogen and its antibiotic sensitivities, providers transition to narrow-spectrum treatment, which helps mitigate resistance development. Broad-spectrum options include Augmentin, clarithromycin, cefdinir, cephalexin, Zithromax, and sulfonamides, while penicillin and amoxicillin are narrow-spectrum agents.