How much paracetamol can I take per day?

Healthy adults can take up to 4,000 mg (4 g) per day, with no more than 1,000 mg per dose and at least 4 hours between doses. If you have liver disease or drink 3+ alcoholic drinks daily, the maximum drops to 2,000 mg per day.

How do I calculate paracetamol dose for a child?

The standard pediatric dose is 10–15 mg/kg per dose, given every 4–6 hours, with a maximum of 75 mg/kg per day. Using the child's actual weight is usually more reliable than age-based guidelines.

Is paracetamol the same as acetaminophen?

Yes. Paracetamol and acetaminophen are the same drug (chemical name: N-acetyl-para-aminophenol). "Paracetamol" is used in most of the world, while "acetaminophen" is the term used primarily in the US, Canada, and Japan.

What are the signs of paracetamol overdose?

Early symptoms (first 24 hours) may be mild — nausea, vomiting, abdominal pain, or no symptoms at all. Liver damage can develop over 24–72 hours, with jaundice, coagulopathy, and potentially fatal hepatic failure. N-acetylcysteine (NAC) is the antidote and is time-sensitive.

Can I take paracetamol and ibuprofen together?

Yes, paracetamol and ibuprofen work through different mechanisms and can be safely alternated or taken together for enhanced pain relief. This combination is especially useful for dental pain, fever in children, and post-surgical pain.

How do I check for hidden acetaminophen in other medications?

Check the "Drug Facts" label of every OTC medication for "acetaminophen" in the active ingredients. Many cold medicines, sleep aids, and prescription painkillers contain 325–500 mg per dose. Add all sources together to stay under 4,000 mg/ day total.

Paracetamol Dosage Calculator

Calculate safe paracetamol (acetaminophen) doses for adults and children by weight. Includes pediatric liquid dosing, liver risk assessment, and combination product warnings.

⚠️ Medical Disclaimer: Paracetamol (acetaminophen) overdose is the leading cause of acute liver failure. Never exceed 4 g/day for healthy adults or 2 g/day with liver disease or chronic alcohol use. Check all combination products for hidden acetaminophen. Seek emergency care if overdose is suspected.

Patient Type

Body Weight

Purpose

Formulation

Single Dose

Doses Per Day

Liver Disease?

Regular Alcohol Use? (3+ drinks/day)

Daily Dose vs Maximum (4,000 mg)

1,500 mg (38%)

Single Dose

500 mg

7.1 mg/kg; Recommended range: 500–1,000 mg

Daily Total

1,500 mg/day

21.4 mg/kg/day across 3 doses

Max Daily Dose

4,000 mg/day

Standard 4,000 mg maximum for healthy adults

Dosing Units

1.0 tablets per dose

500 mg per unit

Minimum Interval

4 hours between doses

Maximum 6 doses per 24 hours

Hepatotoxicity Risk

Low

Toxic threshold ~10,500 mg (10.5 g) in one day

Safety Assessment

✅ Within Safe Range

2,500 mg remaining daily allowance

📋 Pediatric Weight-Based Dosing Chart

Weight (kg)	Age (approx)	Single Dose (15 mg/kg)	Liquid 160mg/5mL	Max Daily
5 kg	3–5 mo	75 mg	2.3 mL	375 mg
8 kg	6–11 mo	120 mg	3.8 mL	600 mg
10 kg	1–2 yr	150 mg	4.7 mL	750 mg
15 kg	2–3 yr	225 mg	7 mL	1,125 mg
20 kg	4–5 yr	300 mg	9.4 mL	1,500 mg
25 kg	6–8 yr	375 mg	11.7 mL	1,875 mg
30 kg	8–10 yr	450 mg	14.1 mL	2,250 mg
40 kg	10–12 yr	500 mg	15.6 mL	3,000 mg

⚠️ Common Combination Products Containing Acetaminophen

Product	Acetaminophen per Unit	Other Active Ingredient
Vicodin / Norco	300–325 mg	Hydrocodone
Percocet	325 mg	Oxycodone
NyQuil	325 mg/15 mL	Doxylamine, DXM
DayQuil	325 mg/15 mL	Phenylephrine, DXM
Excedrin	250 mg	Aspirin, Caffeine
Midol	500 mg	Caffeine, Pyrilamine

Planning notes, formulas, and examples

About the Paracetamol Dosage Calculator

The Paracetamol Dosage Calculator determines safe, weight-based dosing for paracetamol (known as acetaminophen in the US, and sold under brand names including Tylenol, Panadol, and Calpol). It is the most commonly used analgesic and antipyretic worldwide, available in dozens of formulations from infant drops to adult extra-strength tablets, rectal suppositories, and intravenous solutions.

Safe dosing of paracetamol matters because acetaminophen overdose is a major cause of acute liver failure in developed countries. The therapeutic window is narrower than many people realize: the standard maximum of 4,000 mg/day for healthy adults drops to 2,000 mg/day for those with liver disease or chronic alcohol use. Adding to the risk, acetaminophen is hidden in over 600 combination products — cold medicines, sleep aids, prescription opioid combinations — making accidental overdose through "double-dosing" a real concern.

It shows weight-based dosing for both adults and children, converts doses into practical formulation units (tablets or mL of liquid), tracks total daily intake against safe maximums, adjusts limits for liver disease and alcohol use, and includes a reference table of common combination products containing hidden acetaminophen. Pediatric dosing uses the standard 15 mg/kg per dose guideline with a maximum of 75 mg/kg/day.

When This Page Helps

Paracetamol is straightforward at the label level but easy to miscount when several products contain the same ingredient. This calculator tracks the per-dose amount, the daily total, and the effect of liver risk factors so the combined intake can be checked against the intended limit.

How to Use the Inputs

Select whether the patient is an adult, child, or infant.
Enter body weight in kilograms.
Choose the intended purpose (pain, fever, arthritis, etc.).
Select the specific formulation and strength.
Enter the single dose amount in milligrams.
Enter how many doses per day.
Indicate liver disease or regular alcohol use if applicable.
Review max daily dose, safety assessment, and pediatric dosing charts.

Formula used

Pediatric: 10–15 mg/kg per dose every 4–6 hours (max 75 mg/kg/day, not exceeding 4000 mg/day)
Adult: 500–1000 mg per dose every 4–6 hours (max 4000 mg/day)
Liver disease/alcohol: max 2000 mg/day
Hepatotoxicity threshold: ~150 mg/kg in 24 hours
Potentially lethal: ~350 mg/kg in 24 hours

Example Calculation

Result: 375 mg per dose (15 mg/kg); 1500 mg/day (60 mg/kg/day); within safe range of 1875 mg/day max

A 25 kg child receiving 375 mg (15 mg/kg) four times daily totals 1500 mg/day (60 mg/kg/day), which is within the 75 mg/kg/day maximum of 1875 mg. Each dose equals 11.7 mL of 160 mg/5 mL suspension.

Tips & Best Practices

Always check combination products (cold medicines, sleep aids, prescription opioids) for hidden acetaminophen.
Use weight-based dosing for children — age-based charts can significantly under- or over-dose.
Minimum 4 hours between doses, maximum 6 doses in 24 hours.
Take with food to reduce stomach upset, though absorption is slightly delayed.
Reduce to max 2 g/day if you have liver disease, drink heavily, or are malnourished.
Alcohol use can increase liver risk with repeated acetaminophen dosing, so it is worth checking the daily total carefully.

Paracetamol Pharmacology and Mechanism

Despite being used for over a century, the exact mechanism of paracetamol remains debated. It is believed to work primarily through central inhibition of cyclooxygenase (COX) enzymes, particularly a COX-3 variant, and may also modulate the endocannabinoid system and serotonergic pathways. Unlike NSAIDs, paracetamol has minimal anti-inflammatory activity, making it better described as an analgesic and antipyretic rather than a true anti-inflammatory drug. Its advantage over NSAIDs is the absence of gastrointestinal, renal, and platelet toxicity at therapeutic doses.

Hepatotoxicity and the NAC Window

When paracetamol is metabolized normally, about 90% undergoes glucuronidation and sulfation to harmless metabolites. However, 5–10% is oxidized by CYP2E1 to the toxic metabolite NAPQI (N-acetyl-p-benzoquinone imine), which is normally detoxified by glutathione conjugation. In overdose, glutathione stores are depleted, and NAPQI accumulates, causing hepatocellular necrosis. N-acetylcysteine (NAC) is the antidote — it replenishes glutathione and is nearly 100% effective if given within 8 hours of overdose. Effectiveness declines but remains significant up to 72 hours post-ingestion.

Global Naming and Formulations

Paracetamol is sold under over 100 brand names worldwide: Tylenol (US/Canada), Panadol (UK/Australia/Asia), Calpol (UK pediatric), Doliprane (France), Ben-u-ron (Germany/Portugal), Efferalgan (Europe), and Crocin (India). Available formulations include standard tablets, effervescent tablets, liquid suspensions, infant drops with measured droppers, rectal suppositories, and intravenous solution (Ofirmev/Perfalgan) for hospital use. Despite identical active ingredients, formulation concentrations vary significantly between products and countries.

Sources & Methodology

Last updated: March 28, 2026

Methodology

This worksheet converts weight-based acetaminophen/paracetamol ranges into practical liquid or tablet amounts and daily totals.

Sources

FDA acetaminophen labeling (FDA)
MedlinePlus: Acetaminophen (NIH)
NIH LiverTox: Acetaminophen (NIH/NIDDK)

Frequently Asked Questions

Healthy adults can take up to 4,000 mg (4 g) per day, with no more than 1,000 mg per dose and at least 4 hours between doses. If you have liver disease or drink 3+ alcoholic drinks daily, the maximum drops to 2,000 mg per day.