Antibiotics for Children: When They Help, Side Effects, and How to Use Them Safely

How antibiotics work—and when they don't

Antibiotics fight infections caused by bacteria. They do not work against viruses, which cause most common childhood illnesses, including:

• Most coughs, colds, and runny noses
• The flu
• Most sore throats, except strep throat
• Chest colds, or bronchitis, in otherwise healthy children
• Most sinus congestion that comes with a cold

Giving an antibiotic for a viral illness will not help your child feel better or make the illness go away faster. It can cause harm through side effects and antibiotic resistance.

When antibiotics do help

Antibiotics are appropriate for certain infections caused by bacteria. Common examples in children include:

• Strep throat confirmed by a throat swab
• Certain ear infections, especially in younger children or more severe cases
• Bacterial sinus infections, identified by a particular pattern of persistent, worsening, or severe symptoms
• Bacterial pneumonia
• Urinary tract infections
• Some skin infections

For selected mild ear infections, the pediatrician may recommend watchful waiting for 48 to 72 hours while treating pain and watching closely. Sometimes a delayed prescription is provided to fill if symptoms worsen or do not improve within the agreed timeframe.

Short observation may also be an option for certain persistent, nonsevere bacterial sinus infections. It is not a general approach for every bacterial infection.

Watchful waiting requires a clear follow-up plan. It is an evidence-based option for selected children, not a sign that your child is being undertreated. See our ear infection guide for more about when observation may be reasonable.

Why “just in case” is not harmless

Taking antibiotics when they are not needed carries real downsides:

• Side effects with no benefit.
• Antibiotic resistance. Antibiotic use can help resistant bacteria survive and spread, making future infections—in your child or in others—harder to treat. The bacteria become resistant, not your child's body.
• Disruption of healthy gut bacteria, which can lead to diarrhea and other problems.

This is why doctors aim to use antibiotics only when they will help and choose the most targeted medicine that will do the job.

Common side effects

Many antibiotic side effects are mild, but they are common enough that they matter. They can include:

• Diarrhea
• Nausea and vomiting
• Stomach upset
• Skin rash
• Diaper rash or yeast infections, such as thrush, especially in babies and toddlers

Giving some antibiotics with food can reduce stomach upset. Check the specific instructions for your child's medicine, because some work best on an empty stomach.

A rash during antibiotic treatment does not always mean an allergy; the illness itself can also cause a rash. If you suspect a reaction, contact your child's clinician before giving another dose so they can help decide what to do.

When to get help right away

Contact your child's clinician promptly for new hives, swelling, or a suspected medicine reaction. Rapidly worsening swelling or symptoms affecting breathing or swallowing need emergency care.

Other reasons to seek prompt medical care include:

• Severe or bloody diarrhea, especially with belly pain, fever, or signs of dehydration. An antibiotic-related gut infection can sometimes begin even after the antibiotic is finished. Do not wait several days when diarrhea is severe.
• A spreading rash with blistering or peeling skin.
• Worsening symptoms at any time, or no improvement after about 48 to 72 hours of treatment.

For more on recognizing serious allergic reactions, see our allergies in children guide.

How to use antibiotics safely

1. Give the exact dose prescribed. Use an oral dosing syringe or medicine cup marked in milliliters (mL), not a kitchen spoon. Ask the pharmacist to show you the correct amount if you are unsure.
2. Give it on schedule. Follow the label's timing instructions and ask your pharmacist how to space doses.
3. Shake liquid antibiotics as directed before measuring each dose so the medicine is evenly mixed.
4. Give it for the prescribed number of days, unless your child's clinician changes the plan. Do not shorten or extend treatment on your own. Call the clinician or pharmacist if you have concerns.
5. Do not double up after a missed dose. Follow the medicine's missed-dose instructions or ask your pharmacist what to do.
6. If your child spits out or vomits a dose, ask before repeating it. What to do depends on the medicine, timing, and how much was taken. Check the medicine's instructions or contact your pharmacist rather than guessing.
7. Store it correctly. Some liquid antibiotics need refrigeration; others are stored at room temperature. Follow the label and the use-by date after mixing.
8. Keep medicine out of children's reach and sight, in its original child-resistant container.

What not to do

• Never save leftover antibiotics for a future illness. Some liquid may remain even after the prescribed course is completed. Do not keep giving doses just to empty the bottle.
• Never give your child antibiotics prescribed for someone else or share your child's antibiotics with anyone. The wrong medicine or dose can be ineffective or dangerous.
• Never use an old or expired prescription.
• Do not pressure the doctor for an antibiotic when your child has a viral illness. Ask instead how to relieve symptoms and which warning signs should prompt a call back.

How to dispose of leftover antibiotics

A medicine take-back program is the preferred option. Ask your pharmacy about a nearby drop-off site or mail-back option.

If take-back is not available, check the medicine's disposal instructions or ask your pharmacist. Most medicines that are not on the FDA's flush list can be mixed with used coffee grounds, dirt, or cat litter, sealed in a bag or container, and put in the household trash. Remove personal information from the empty packaging.

Do not pour medicine down a drain or flush it unless the official disposal instructions specifically direct you to do so.

Helping your child feel better without antibiotics

For viral illnesses, comfort care is often the right treatment:

• Plenty of fluids and rest
• Fever and pain relief with acetaminophen or ibuprofen when appropriate for your child's age and weight. Do not give ibuprofen to infants under 6 months without medical advice. Our Fever in Children guide includes weight-based dosing tables.
• Saline nose drops or spray and a cool-mist humidifier for congestion. Clean the humidifier according to its instructions.
• Honey for cough in children 1 year and older. Never give honey to a baby younger than 1 year.

Questions worth asking your child's doctor

• Does my child's illness need an antibiotic, or is it likely viral?
• If not now, what symptoms should make me call back?
• How and when should I give this medicine, and with or without food?
• How long should treatment continue?
• What side effects should I watch for, and when should I call you?

When you and your child's doctor use antibiotics thoughtfully, your child gets the right treatment—and these important medicines stay effective for the times they are truly needed.