Metronidazole Children Dosage: What Parents Need to Know

Metronidazole is a common antibiotic for infections like giardiasis and bacterial vaginosis. Kids need the right amount to clear the bug without side effects. This guide breaks down how to figure the dose, when to give it, and what to watch for.

How the dose is calculated

The standard way doctors set the dose is by weight. They usually use 7.5 to 15 mg per kilogram of body weight each day, split into two or three doses. For example, a child who weighs 20 kg could get 150 mg (20 kg × 7.5 mg) twice a day, or 300 mg once a day if the doctor prefers a single dose schedule.

Always follow the exact prescription your doctor writes. If the label says 250 mg tablets, you may need to cut the tablet in half or use a liquid formulation to reach the right amount. Liquid metronidazole typically comes as 100 mg/5 mL, so you can measure the dose with a medicine spoon or syringe.

Duration matters too. Most infections need 5 to 7 days of treatment, but some conditions like anaerobic abdominal infections might need 10 days. Stopping early can let the infection come back.

Key safety tips

Give the medicine with food or milk to reduce stomach upset. If your child feels nauseous, a small snack can help. Keep an eye out for side effects such as a metallic taste, mild diarrhea, or a rash. These are usually not serious, but tell the doctor if they get worse.

Never mix metronidazole with alcohol, even in small amounts. Alcohol can cause a severe reaction with flushing, rapid heart rate, and nausea. This rule applies while your child is taking the drug and for at least 48 hours after the last dose.

If you miss a dose, give it as soon as you remember—unless it’s almost time for the next dose. In that case, skip the missed one and continue on schedule. Don’t double up because it can increase the chance of side effects.

Store the medication at room temperature, away from moisture and heat. Keep it out of reach of children, just like any other medicine.

Finally, keep the follow‑up appointment. The doctor may want to check that the infection is gone or adjust the dose if the child’s weight has changed.

With the right dose, proper timing, and a few safety checks, metronidazole works well for kids. If you have any doubts, call your pharmacist or doctor—better safe than sorry.