Weight-based OTC dosing for acetaminophen, ibuprofen, and diphenhydramine with exact ml amounts and an alternating fever schedule.
Children's medication doses are typically calculated based on body weight (mg per kg) because children metabolize drugs differently than adults and their smaller body size means adult doses can be dangerous. The dose is calculated as: weight in kg x dose per kg = total dose. This total dose is then divided based on the dosing frequency (e.g., every 6 or 8 hours) to determine each individual dose.
Enter the child's weight (in pounds or kilograms) and select the medication. The calculator shows the recommended dose per administration, frequency, and maximum daily dose based on standard pediatric dosing guidelines. It converts between weight units automatically. This calculator covers common over-the-counter medications including acetaminophen (Tylenol) and ibuprofen (Advil/Motrin) for pediatric use.
Always use the dosing device that comes with the medication (oral syringe or dosing cup) rather than household spoons, which are inaccurate. Never exceed the maximum daily dose. Weight-based dosing is more accurate than age-based dosing, especially for children who are larger or smaller than average for their age. If your child is taking multiple medications, check for ingredient overlap (many cold/flu products contain acetaminophen). When in doubt, call your pediatrician or pharmacist.
Children are not simply "small adults" when it comes to medication dosing. Pediatric doses are typically calculated based on body weight (mg/kg) or body surface area (mg/m2) because children metabolize drugs differently than adults. Their higher body water percentage, immature liver enzyme systems, and faster metabolic rates relative to body size all affect drug pharmacokinetics. The most common weight-based dosing formula is: dose = patient weight (kg) x dose per kg x frequency.
Common pediatric medications and their typical weight-based doses include: acetaminophen (10-15 mg/kg every 4-6 hours, max 5 doses/day), ibuprofen (5-10 mg/kg every 6-8 hours for children over 6 months), amoxicillin (25-45 mg/kg/day divided into 2-3 doses for standard infections, up to 80-90 mg/kg/day for resistant infections). Dosing errors are among the most common medication errors in pediatrics, which is why weight verification and double-checking calculations are standard practice.
This calculator provides estimates based on standard dosing guidelines. Actual prescribed doses may differ based on the specific condition being treated, drug interactions, organ function, and the child's individual response. Never substitute calculator output for a healthcare provider's prescription. Always use the measuring device provided with the medication (oral syringe, dosing cup) rather than household spoons, which vary significantly in volume. The FDA recommends using metric measurements (mL) exclusively for liquid pediatric medications to reduce dosing errors. For questions about a specific medication or dosing concern, contact your child's pediatrician or a pharmacist.
Age-based dosing guidelines are sometimes used as a secondary check but should not replace weight-based calculations. Children of the same age can vary dramatically in weight (a normal 5-year-old may weigh anywhere from 33 to 55 pounds), making age-based dosing imprecise. For over-the-counter medications, the weight-based ranges printed on packaging are generally reliable but should be followed carefully. When in doubt between two dosing options on the packaging, using the lower dose is safer. The BMI Calculator can help track whether a child falls within normal weight ranges for their age, which provides context for dosing conversations with healthcare providers.