Pediatric medication dosage calculator.
Weight-based dosing for the most common over-the-counter medications used for infants and toddlers — including acetaminophen (also called paracetamol outside the US), ibuprofen, and antihistamines. Always confirm with your provider for your child’s specific situation.
Three rules that matter every time
Always dose by weight, not age
Package labels show age ranges as a guide, but the correct dose is always based on your child’s current weight. Two children the same age can need very different amounts.
Use the right measuring tool
Always use the dosing syringe or cup that comes with the medication. A kitchen teaspoon is not accurate enough. If the packaging didn’t include one, ask your pharmacist for one.
Check the concentration
Children’s and infant formulations of the same drug can have different concentrations. Always read the label carefully — the dose changes depending on which product you have.
Calculate the right dose for your child
Enter your child’s weight to get weight-based dosing guidance for the most common pediatric medications.
Common medications for infants and toddlers
What each medication is for, when to use it, and what to watch out for. If a parent outside the US is searching for paracetamol — that’s the same drug as acetaminophen, just the name used in most other countries.
Acetaminophen
Also known as: paracetamol, Tylenol, Children’s Tylenol, Feverall, Tempra, Panadol, CalpolWhat it’s used for
Fever reduction and mild to moderate pain relief — teething pain, ear pain, headaches, and post-vaccination soreness.
Standard dose
10–15 mg per kg of body weight every 4–6 hours as needed. Do not exceed 5 doses in 24 hours.
Common brand names
Available forms
Infant drops (160 mg/5 mL), children’s liquid suspension, chewable tablets, suppositories.
Ibuprofen
Also known as: Advil, Motrin, Children’s Motrin, NurofenWhat it’s used for
Fever reduction and pain relief — works better than acetaminophen for inflammation-related pain. Tends to last longer (6–8 hours vs. 4–6 hours).
Standard dose
5–10 mg per kg of body weight every 6–8 hours as needed. Do not exceed 4 doses in 24 hours.
Common brand names
Available forms
Children’s liquid suspension (100 mg/5 mL), chewable tablets. Give with food or milk to reduce stomach upset.
Diphenhydramine
Also known as: Benadryl, Children’s BenadrylWhat it’s used for
Allergic reactions, hives, hay fever symptoms, and itching. Sometimes used for motion sickness. Not recommended as a sleep aid.
Standard dose (2 years+)
1 mg per kg of body weight every 6 hours as needed. Maximum 50 mg per dose.
Common brand names
Available forms
Children’s liquid (12.5 mg/5 mL), chewable tablets, regular tablets.
Loratadine
Also known as: Claritin, Children’s Claritin, AlavertWhat it’s used for
Seasonal allergies, hay fever, hives, and allergic rhinitis. Non-drowsy for most children — a good first choice for daytime allergy relief.
Standard dose
Ages 2–5: 5 mg once daily. Ages 6+: 10 mg once daily.
Common brand names
Available forms
Children’s syrup (5 mg/5 mL), chewable tablets, dissolving tablets.
Cetirizine
Also known as: Zyrtec, Children’s Zyrtec, ReactineWhat it’s used for
Seasonal and year-round allergies, hives, and allergic rhinitis. Works within 1 hour and lasts 24 hours. Slightly more likely to cause drowsiness than loratadine.
Standard dose
Ages 2–5: 2.5 mg once daily. Ages 6+: 5–10 mg once daily.
Common brand names
Available forms
Children’s syrup (5 mg/5 mL), chewable tablets, dissolving tablets.
Simethicone
Also known as: Mylicon, Infants’ Gas Relief DropsWhat it’s used for
Relieves infant gas and bloating-related fussiness, often from air swallowing during feeds or certain formulas.
Standard dose
Under 24 lb: 0.3 mL (20 mg). 24 lb and over: 0.6 mL (40 mg). Give after meals and at bedtime as needed. Do not exceed 12 doses in 24 hours.
Common brand names
Available forms
Infant drops (20 mg/0.3 mL), dosed by dropper or oral syringe.
Guaifenesin
Also known as: Mucinex Children’s, Robitussin Chest Congestion (plain formulas only)What it’s used for
Loosens and thins mucus in the chest to make a wet, productive cough more effective. It’s an expectorant, not a cough suppressant.
Standard dose
Ages 4–6: 5 mL (100 mg) every 4 hours. Ages 6–12: 5–10 mL (100–200 mg) every 4 hours. Do not exceed 6 doses in 24 hours.
Common brand names
Available forms
Children’s liquid (100 mg/5 mL). Only the plain, single-ingredient product follows this dosing.
Oral rehydration solution
Also known as: Pedialyte, EnfalyteWhat it’s used for
Replaces fluids and electrolytes lost to vomiting, diarrhea, or fever — helps prevent dehydration during a stomach bug or illness.
General guidance
Offer in small, frequent sips rather than a large amount at once. After each loose stool or vomiting episode: under 2 years, about 2–4 oz (60–120 mL); ages 2–10, about 4–8 oz (120–240 mL); over 10, as much as tolerated.
Common brand names
Available forms
Ready-to-drink liquid, freezer pops, powder packets mixed with water.
Medications not safe for infants and toddlers
Some common medications that are safe for older children and adults should never be given to infants or toddlers.
Aspirin
Never give aspirin to anyone under 18 with a viral illness — it’s linked to Reye’s syndrome, a rare but serious condition affecting the liver and brain.
Codeine and tramadol
These opioid pain relievers are not approved for children under 12 and carry serious breathing risks. Do not use them in young children under any circumstances.
Adult-strength formulations
Never split or crush adult tablets to create a smaller dose. The formulations are different and the concentrations are not designed for children’s weight ranges.
Cough and cold medicines under 4
The FDA recommends against using over-the-counter cough and cold medicines in children under 4 years old — they are not effective and can cause serious side effects.
Sinarest and similar combination cold products
Sinarest is a multi-ingredient formula (acetaminophen/paracetamol plus a decongestant and an antihistamine) sold in India and not available or FDA-approved in the US. Because it already contains acetaminophen, giving it alongside a separate Tylenol or paracetamol dose risks double-dosing — and like other combination cough-and-cold products, it falls under the same under-4 caution above.
See it. Share it. Sort it.
Log medications and doses in MamaBear alongside symptoms — and share the complete picture with your provider.