| Generic name |
Mefenamic acid |
| Brand names |
Ponstel®, Ponstel® Oral Disintegrating Tablet (ODT), Mefenac®, Mefenac ODT, Mefenac Disintegrating Tablet, and a handful of generic versions sold in various countries (e.g., Mefenac in India, Meferol in Mexico, Mefenac in Brazil). |
| Common indications |
• Acute or chronic pain (e.g., dental, muscular, or joint pain)
• Primary dysmenorrhea (painful menstruation)
• Menstrual cramps
• Menstrual pain in premenopausal women |
| Mechanism of action |
Inhibits cyclooxygenase (COX‑1 & COX‑2) → reduces prostaglandin synthesis → decreases inflammation, pain, and fever. |
| Typical dosing (adult) |
• 200 mg orally every 6–8 hours as needed
• Do not exceed 800 mg in a 24‑hour period unless directed by a clinician.
• For dysmenorrhea: 400 mg taken 2–3 times daily during the first 3–5 days of menstruation. |
| Administration |
Oral tablets or oral disintegrating tablets (ODT) that dissolve on the tongue. Take with a full glass of water. If you have a stomach lining sensitivity, take with food or a proton‑pump inhibitor if prescribed. |
| Common side effects |
• Gastro‑intestinal upset (nausea, abdominal pain, heartburn)
• Headache
• Dizziness
• Rash or itching (rare)
• Rare: GI bleeding or ulcers, especially with long‑term use or in older adults |
| Contraindications |
• Known hypersensitivity to mefenamic acid or other NSAIDs
• Active peptic ulcer disease
• Severe renal or hepatic impairment
• Severe heart failure or uncontrolled hypertension
• Pregnant women (especially third trimester) and nursing mothers (excretion in breast milk) |
| Drug interactions |
• Anticoagulants (warfarin, rivaroxaban): ↑ bleeding risk
• Other NSAIDs: ↑ GI toxicity
• ACE inhibitors/ARBs: ↑ risk of renal impairment
• SSRIs: ↑ GI bleeding
• Corticosteroids: ↑ GI ulcers |
| Special populations |
• Children & Adolescents: Approved for dysmenorrhea in patients ≥12 y in some countries; otherwise off‑label. Dose usually 5 mg/kg up to a max of 400 mg.
• Elderly: Lower starting dose (200 mg) and watch for GI, renal, or cardiovascular side effects. |
| Over‑the‑counter availability |
In many countries mefenamic acid is a prescription‑only NSAID due to potential GI and cardiovascular risks. Some countries offer it in lower‑dose OTC forms (e.g., 100 mg tablets) for short‑term use, but check local regulations. |
| Generic vs brand |
The generic formulation contains the same active ingredient (mefenamic acid) in the same strength and dosage form as the brand‑name product. Generics are typically less expensive and are required by regulatory agencies to have the same bioavailability, purity, and efficacy. |