Which to choose?
Paracetamol first for almost everything: mild to moderate pain, fever, pregnancy, breastfeeding, anticoagulated patients. Metamizole when a doctor prescribes it for severe or colicky pain, as a short course. Metamizole is not licensed in the UK or the US; if fever, sore throat or mouth ulcers appear while taking it, stop and seek advice the same day.
Point-by-point comparison
Brands: Panadol · Calpol
| Paracetamol | Metamizole | |
|---|---|---|
| Mechanism | Inhibits central prostaglandin synthesis. NOT anti-inflammatory. | Potent analgesic and antipyretic with an antispasmodic effect. Almost no anti-inflammatory action. |
| Indications | Mild to moderate pain, fever. | Moderate to severe acute pain, colicky pain, high fever not responding to other drugs. |
| Adult dose | 500-1000 mg every 6-8 h. Max 3 g/day. | 500-1000 mg up to 4 times a day. Max 4 g/day. Short courses. |
| Onset of effect | 30-60 min | 30-60 min |
| Duration of effect | 4-6 h | 6-8 h |
| Pregnancy | Compatible — first choice. | Avoid in the 1st and 3rd trimesters (contraindicated in the 3rd). |
| Breastfeeding | Compatible. | Avoid. |
| Paediatric use | From birth, by weight. | Prescription only. Contraindicated under 3 months or under 5 kg. |
| Advantages | The safest: no gastric or renal harm, first choice in pregnancy, breastfeeding and anticoagulated patients. Over the counter. | More effective than paracetamol for severe and colicky pain. No NSAID-type gastric harm. |
| Disadvantages | Liver toxicity in overdose. Less effective for severe and colicky pain. | Agranulocytosis (rare but serious): short courses, blood count if it goes on. Hypotension. Prescription-only. |
Source: Spanish SmPC and 2018 safety note (AEMPS)
Frequently asked questions
Which is better, paracetamol or metamizole?
Paracetamol first for almost everything: mild to moderate pain, fever, pregnancy, breastfeeding, anticoagulated patients. Metamizole when a doctor prescribes it for severe or colicky pain, as a short course. Metamizole is not licensed in the UK or the US; if fever, sore throat or mouth ulcers appear while taking it, stop and seek advice the same day.
Can paracetamol or metamizole be taken in pregnancy?
Paracetamol: Compatible — first choice. Metamizole: Avoid in the 1st and 3rd trimesters (contraindicated in the 3rd). Always ask a doctor or pharmacist before taking a medicine in pregnancy.
And while breastfeeding?
Paracetamol: Compatible. Metamizole: Avoid.