Paracetamol: doses, limits and hidden overdose

Every question, with the answer explained

The full set, for revision or for reading straight through. The correct answer is marked, and the explanation says why.

1. 1. What is the usual maximum paracetamol dose for a healthy adult in 24 hours?

   • 2 g
   • 4 g (for example 1 g four times a day)
   • 8 g
   • There is no limit

   4 g (for example 1 g four times a day). 4 grams in 24 hours is the usual ceiling for a healthy adult, with at least four hours between doses. Lower limits apply to people with low body weight, liver disease or regular alcohol use.

2. 2. Which organ does paracetamol overdose damage?

   • The liver
   • The lungs
   • The stomach lining
   • The kidneys only

   The liver. Overdose overwhelms the liver's ability to detoxify a metabolite, and cells die. Damage builds over a day or two, often after the person feels fine.

   What does “liver function test” mean?

3. 3. How does accidental paracetamol overdose most often happen?

   • Taking a single very large dose deliberately
   • Taking several combination cold or flu products that each contain paracetamol
   • Taking it on an empty stomach
   • Taking it with water

   Taking several combination cold or flu products that each contain paracetamol. Many cold, flu and pain combination products contain paracetamol under other names. Stacking two or three of them, each 'as directed', quietly exceeds the daily limit.

4. 4. In the first hours after a paracetamol overdose, a person usually:

   • Collapses immediately
   • Feels well or only mildly nauseated
   • Has severe chest pain
   • Loses consciousness

   Feels well or only mildly nauseated. The dangerous feature of paracetamol overdose is how well people feel early on. Treatment works best within 8 hours, so go to hospital on the fact of the overdose, not on symptoms.

5. 5. How is a child's paracetamol dose calculated?

   • By age alone
   • By weight
   • By height
   • The adult dose halved

   By weight. Paediatric dosing is by weight — commonly 15 mg per kg per dose. Two children of the same age can need noticeably different amounts.

6. 6. Compared with ibuprofen, paracetamol:

   • Is harsher on the stomach
   • Is gentler on the stomach and safer in dengue and in most kidney disease
   • Is an antibiotic
   • Reduces inflammation more

   Is gentler on the stomach and safer in dengue and in most kidney disease. Paracetamol is not an anti-inflammatory. That makes it weaker for inflammatory pain but safer for stomachs, kidneys and bleeding risk — which is why it is preferred in dengue.

   What does “nsaid” mean?

7. 7. Who should take less than the standard maximum?

   • People with liver disease, low body weight or regular heavy alcohol use
   • Tall people
   • Children over 12
   • Nobody

   People with liver disease, low body weight or regular heavy alcohol use. Liver disease, malnutrition, low body weight and regular alcohol all reduce the safe ceiling. Ask your doctor what your own limit is.

8. 8. If someone has taken too much paracetamol, what should you do?

   • Wait to see if symptoms appear
   • Go to hospital immediately, even if they feel well
   • Give milk and wait
   • Give a second dose later

   Go to hospital immediately, even if they feel well. The antidote works best within 8 hours and loses effect after that. Waiting for symptoms wastes the window in which the liver can still be protected.