Period pain is cramping or aching in the lower tummy (sometimes also felt in the back or thighs) around the time of a period. It’s very common and is often caused by the womb contracting as it sheds its lining. Many people can manage symptoms with self-care measures such as heat (hot water bottle/heat pad), gentle exercise, massage, and suitable pain relief.

Period pain can be:

Primary dysmenorrhoea (most common): period pain not linked to an underlying condition.
Secondary dysmenorrhoea: period pain caused by an underlying condition (for example, some people notice pain becomes worse or changes after years of “normal” periods). If pain is severe, sudden, getting worse, or stops someone doing day-to-day activities, they should speak to a clinician to rule out an underlying cause.

Period pain is commonly caused by the womb (uterus) contracting to push out the womb lining. These contractions are driven by natural chemicals called prostaglandins; if more prostaglandins are released, contractions can be stronger and more painful.

• Feminax (e.g., Feminax Express)
  • Contains ibuprofen (as ibuprofen lysine), an anti-inflammatory painkiller (NSAID) used to relieve period pain and cramps

• Feminax Ultra
  • Contains naproxen 250 mg, an NSAID specifically licensed for period pain (dysmenorrhoea) in the appropriate age group.
• Mefenamic Acid 
  • An NSAID commonly used for menstrual cramps; it works by reducing prostaglandins/inflammation linked to pain.

Important safety note for patients (high-level): Because these are NSAIDs, they’re not suitable for everyone (for example, some people with certain stomach ulcer history, specific kidney problems, or NSAID sensitivity/asthma triggers may need alternatives).