Period cramps: which painkillers actually work, and which ones don't

Period cramps affect more than half of women of reproductive age every month, yet many people reaching the pharmacy shelf still pick the wrong product. BBC News reports that paracetamol, by far the most commonly bought analgesic, is consistently outperformed by nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, naproxen and mefenamic acid when it comes to menstrual pain.

The reason lies in the biology of the cramp itself. During menstruation, cells in the lining of the uterus release prostaglandins, chemicals that drive the contractions which shed the lining. In severe cases the pain can rival that of a heart attack. Because NSAIDs block prostaglandin production directly, they reduce both the intensity and duration of contractions. Paracetamol, by contrast, does not meaningfully suppress prostaglandins, so its effect on cramps is limited.

Timing may matter as much as the choice of drug. Clinicians interviewed by the BBC emphasise that taking an NSAID at the first sign of bleeding, or even slightly before, allows the medicine to stop prostaglandins building up. The same dose taken after cramps have already settled in tends to disappoint. That delay may explain why many women conclude painkillers "don't work" for them.

Dose matters too. For ibuprofen, the usual recommendation is 400 mg every six to eight hours while symptoms last. Naproxen lasts longer in the body and is often a practical choice for night-time pain at 250 to 500 mg twice daily. Mefenamic acid, available on prescription in the UK, is another option clinicians frequently reach for.

NSAIDs are not for everyone. Women with a history of stomach ulcers, severe asthma, kidney impairment or who are on blood-thinning medication should avoid them. In those cases paracetamol, or a low-dose combination product, may be appropriate, though women should expect smaller benefits.

A further point clinicians stress is that hormonal treatment, rather than painkillers, often offers the most durable relief. The combined contraceptive pill, hormonal intrauterine devices and certain progestin patches all reduce the lining and the prostaglandins that come with it. Gynaecologists interviewed by the BBC suggest that any woman caught in a monthly cycle of high-dose analgesics should discuss these options with their doctor.

Non-drug methods carry good evidence too. Heat packs, warm compresses, yoga and regular aerobic exercise have all shown benefit in randomised studies, with applied heat in some trials reaching ibuprofen-level relief. Magnesium and low-dose vitamin B1 help some women, though large trial evidence is more mixed.

There are red flags that warrant a closer look. Pain that persists outside menstruation, pain during intercourse or pain that has worsened steadily across years may indicate endometriosis or adenomyosis. The BBC and the UK Royal College of Obstetricians and Gynaecologists urge women whose pain disrupts daily life or causes lost work days not to delay a gynaecological assessment.

The overall message is straightforward: the conversation should be less about which pill, and more about when and why. Used correctly and on time, the right drug makes period pain manageable for most women, decades of evidence suggest.

This article is not medical advice. If you experience regular or severe menstrual pain, consult a general practitioner or gynaecologist.