Paracetamol 500 vs 650: what’s the difference, and which one should you take?

Almost every Indian home has a strip of paracetamol somewhere, often two different ones: a 500 and a 650. When the fever comes at 2 am, which one do you reach for?

Same medicine, different amount

Brands like Dolo 650, Calpol 650, Crocin and Doliprane 650 all contain paracetamol, also called acetaminophen. The number is the amount in each tablet. A 650 mg tablet has 150 mg more than a 500 mg tablet. That is the whole difference: not a different medicine, not “stronger” in any other way.

Which one is right for you

• Your doctor may suggest 650 mg for an adult with a high fever or body ache, and 500 mg for a smaller adult, an older person or for milder symptoms.
• Children need a dose based on their weight, usually as a syrup or drops. Never cut adult tablets for a child; use the children’s product and the syringe or cup that comes with it.
• If you have liver disease, drink alcohol regularly, are underweight or take other medicines, ask a doctor or pharmacist for the right dose first.

The rule that matters most: the daily limit

Paracetamol is very safe at the right dose and dangerous above it, because too much can damage the liver. For most healthy adults the limit is 4,000 mg in 24 hours, with at least 4 hours between doses. That is six 650 mg tablets at the very most, and many doctors advise staying lower.

The common mistake is taking paracetamol twice without knowing it. Many cold and flu tablets and syrups already contain paracetamol. Before you take a second product, read the composition on the pack.

When to stop self-treating

• Fever above 39°C (102°F) that does not come down, or lasts more than 3 days.
• Severe headache with a stiff neck, a rash, confusion or breathing trouble.
• During the monsoon, a high fever with body pain could be dengue; see a doctor and avoid ibuprofen and aspirin until dengue is ruled out (more on monsoon health).

This article is general information, not medical advice. If you are worried about your health or someone else’s, speak to a doctor.