Mefenamic Acid – Specialized NSAID for menstrual pain and heavy bleeding.
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What is Mefenamic Acid?
Mefenamic acid is particularly effective for women’s health issues, offering superior relief for menstrual pain and reduction of heavy periods compared to standard painkillers. Its specific action on menstrual-related prostaglandins makes it a specialized choice for period-related symptoms.
Book an online consultation if you’re experiencing severe period pain, heavy menstrual bleeding, or period-related symptoms that interfere with your daily life. Our GPs can assess your menstrual health and determine if Mefenamic acid or other treatments are appropriate for your specific menstrual concerns.
What is Mefenamic Acid used for?
- Menstrual pain (dysmenorrhea)
- Heavy menstrual bleeding (menorrhagia)
- Period-related pain and discomfort
- Mild to moderate pain relief
- Post-partum pain
- Dental pain
- Musculoskeletal pain
How does Mefenamic Acid work?
A fenamate NSAID that inhibits cyclooxygenase enzymes, reducing prostaglandin production. It's particularly effective for menstrual symptoms as it specifically targets the prostaglandins involved in uterine contractions and heavy bleeding.
Dosage and Administration
Adults
500mg three times daily with food. For menstrual pain: start 2-3 days before expected period and continue for 2-3 days after bleeding stops. Maximum 7 days per cycle.
Children
Children over 12 years: adult dose. Not recommended under 12 years.
Important Notes
- Always take with food to reduce stomach irritation.
- For periods: start before bleeding begins for best effect.
- Don't exceed 7 days of continuous use.
- Use shortest effective duration to minimize side effects.
Side Effects
Common Side Effects
- Stomach upset and nausea
- Indigestion and heartburn
- Diarrhea
- Headache
- Dizziness
- Skin rash
Serious Side Effects
Seek immediate medical attention if you experience:
- Stomach ulcers and bleeding
- Kidney problems
- Liver problems
- Severe allergic reactions
- Blood disorders
- Cardiovascular events (rare)
Important Warnings
- Take with food to reduce stomach irritation and ulcer risk.
- Not suitable for people with stomach ulcers, severe heart, kidney, or liver disease.
- Tell your GP if you develop stomach pain, black stools, or unusual bleeding.
- Use with caution in elderly patients (increased risk of side effects).
- Avoid if you're trying to conceive as it may affect fertility.
Drug Interactions
Tell your GP if you're taking any of the following medications:
- Warfarin and anticoagulants—increased bleeding risk.
- ACE inhibitors—may reduce their effectiveness and affect kidneys.
- Lithium—may increase lithium levels.
- Methotrexate—increased risk of toxicity.
- Other NSAIDs—increased risk of side effects, avoid combination.
Frequently Asked Questions
How is Mefenamic acid different from other painkillers for periods?
It specifically targets the prostaglandins that cause period pain and heavy bleeding, making it more effective than paracetamol and often better than other NSAIDs for menstrual symptoms.
Should I start taking it before my period begins?
Yes, starting 2-3 days before expected bleeding gives the best results as it prevents the buildup of prostaglandins that cause pain and heavy bleeding.
Can Mefenamic acid reduce heavy periods?
Yes, it can reduce menstrual blood loss by 20-50% by reducing the prostaglandins that contribute to heavy bleeding, making it useful for both pain and bleeding.
How long can I use Mefenamic acid for period pain?
Use for the shortest time needed each cycle (usually 2-5 days). Long-term daily use isn't recommended due to increased side effect risks.
Medically Reviewed by: Mohammed Hassan - Independent Prescriber
Last Updated: 2025-01-14