OTC Dosing Charts
Weight-based dosing for the three most common over-the-counter medications we get questions about. Print this page, or save it on your phone for the middle of the night.
Always dose by weight, not age. Use a syringe or measuring cup — never a kitchen spoon. If you're unsure or your child is under 3 months old with a fever (≥ 100.4 °F / 38 °C rectal), call us at (555) 555-0100 before giving anything.
Acetaminophen (Tylenol)
10–15 mg/kg every 4–6 hours
Safe from any age (with provider OK under 3 months). Maximum 5 doses in 24 hours. Liquid concentration shown is the standard infants' / children's suspension: 160 mg per 5 mL (these are the same product since 2011 — no separate "infant drops" anymore).
| Weight | Approx. age | Dose | Liquid (160 mg / 5 mL) | Chewable (80 mg) |
|---|---|---|---|---|
| 6–11 lb 2.7–5 kg | 0–3 mo | Call office before giving | — | — |
| 12–17 lb 5.4–7.7 kg | 4–11 mo | 80 mg | 2.5 mL | — |
| 18–23 lb 8–10.5 kg | 12–23 mo | 120 mg | 3.75 mL | — |
| 24–35 lb 10.9–15.9 kg | 2–3 yr | 160 mg | 5 mL (1 tsp) | 2 tablets (80 mg) |
| 36–47 lb 16.3–21.4 kg | 4–5 yr | 240 mg | 7.5 mL | 3 tablets (80 mg) |
| 48–59 lb 21.8–26.8 kg | 6–8 yr | 320 mg | 10 mL (2 tsp) | 4 tablets (80 mg) |
| 60–71 lb 27.3–32.3 kg | 9–10 yr | 400 mg | 12.5 mL | 5 tablets (80 mg) |
| 72–95 lb 32.7–43.2 kg | 11 yr | 480 mg | 15 mL (3 tsp) | 6 tablets (80 mg) |
| 96+ lb 43.6+ kg | 12+ yr | 640 mg (max 1000 mg/dose adult) | — | Use adult-strength 325–500 mg |
Ibuprofen (Motrin / Advil)
10 mg/kg every 6–8 hours
Do not give to infants under 6 months. Maximum 4 doses in 24 hours. Give with food or milk to reduce stomach upset. Two common liquid strengths: infant drops 50 mg/1.25 mL and children's suspension 100 mg/5 mL.
| Weight | Approx. age | Dose | Infant drops (50 mg / 1.25 mL) | Children's liquid (100 mg / 5 mL) | Chewable / tablet (100 mg) |
|---|---|---|---|---|---|
| Under 12 lb Under 5.4 kg | Under 6 mo | Do NOT give — under 6 months is unsafe | — | — | — |
| 12–17 lb 5.4–7.7 kg | 6–11 mo | 50 mg | 1.25 mL | 2.5 mL | — |
| 18–23 lb 8–10.5 kg | 12–23 mo | 75 mg | 1.875 mL | 3.75 mL | — |
| 24–35 lb 10.9–15.9 kg | 2–3 yr | 100 mg | — | 5 mL (1 tsp) | 1 tablet (100 mg) |
| 36–47 lb 16.3–21.4 kg | 4–5 yr | 150 mg | — | 7.5 mL | 1½ tablets |
| 48–59 lb 21.8–26.8 kg | 6–8 yr | 200 mg | — | 10 mL (2 tsp) | 2 tablets |
| 60–71 lb 27.3–32.3 kg | 9–10 yr | 250 mg | — | 12.5 mL | 2½ tablets |
| 72–95 lb 32.7–43.2 kg | 11 yr | 300 mg | — | 15 mL (3 tsp) | 3 tablets |
| 96+ lb 43.6+ kg | 12+ yr | 400 mg (adult dose) | — | — | Use adult 200 mg tablets (2 tabs) |
Diphenhydramine (Benadryl)
1 mg/kg every 6 hours
Do not give to children under 2 years without specific direction from your pediatrician. The AAP also discourages diphenhydramine for colds or as a sleep aid — it can cause paradoxical agitation or, rarely, dangerous breathing changes in young children. Use it for true allergic reactions only. Standard liquid is 12.5 mg per 5 mL.
| Weight | Approx. age | Dose | Liquid (12.5 mg / 5 mL) | Chewable (12.5 mg) |
|---|---|---|---|---|
| Any Any | Under 2 yr | Do NOT give without provider direction | — | — |
| 20–24 lb 9–10.9 kg | ~2 yr | 6.25 mg | 2.5 mL (½ tsp) | — |
| 25–37 lb 11.3–16.8 kg | 3–5 yr | 12.5 mg | 5 mL (1 tsp) | 1 chewable (12.5 mg) |
| 38–49 lb 17.2–22.2 kg | 5–7 yr | 18.75 mg | 7.5 mL | 1½ chewables |
| 50–99 lb 22.7–44.9 kg | 8–11 yr | 25 mg | 10 mL (2 tsp) | 2 chewables |
| 100+ lb 45+ kg | 12+ yr | 50 mg | 20 mL (4 tsp) | 4 chewables |
When to call us
- Any fever in an infant under 3 months (rectal ≥ 100.4 °F / 38 °C).
- Fever over 104 °F (40 °C) at any age.
- Fever lasting more than 3 days, or returning after a fever-free stretch.
- Child is hard to wake, dehydrated (no wet diapers ≥ 8 hours), or refusing fluids.
- Breathing fast, working hard to breathe, or wheezing.
- You're just not sure — that's always a fine reason to call.
Sources & reviewed
Dosing tables are derived from the American Academy of Pediatrics (HealthyChildren.org) acetaminophen and ibuprofen dosing tables, along with the published manufacturer dosing charts for Children's Tylenol, Children's Motrin, and Children's Benadryl. Last reviewed by the Luma Pediatrics clinical team: November 2025.
This page is a quick reference for parents and is not a substitute for personalized medical advice. For urgent concerns call (555) 555-0100, or go to the nearest emergency room. For poison-related questions, call Poison Control at 1-800-222-1222.