Please check your internet connection and try again.
# Mefenamic Acid
## Overview
Mefenamic acid is a nonsteroidal anti-inflammatory drug (NSAID) used for the short-term relief of mild to moderate pain.
## Primary Indications
* Pain associated with osteoarthritis
* Pain associated with rheumatoid arthritis (adjunctive therapy)
* Dysmenorrhea
## Adult Dosing
* **Pain:** 500 mg every 6 hours as needed. Maximum daily dose: 1500 mg.
* **Dysmenorrhea:** 500 mg every 6 hours as needed, starting at the onset of pain and bleeding. Maximum daily dose: 1500 mg.
* Treatment should not exceed 7 days.
## Pediatric Dosing
Mefenamic acid is generally not recommended for children under 14 years of age due to lack of established safety and efficacy.
## Dose Adjustments
No specific dose adjustments are recommended for renal or hepatic impairment, but caution is advised due to potential for drug accumulation and toxicity. Use the lowest effective dose for the shortest duration.
## Contraindications
* Hypersensitivity to mefenamic acid, aspirin, other NSAIDs, or any component of the formulation.
* History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs.
* Perioperative pain in the setting of coronary artery bypass graft (CABG) surgery.
## Adverse Effects
* **Common:** Diarrhea, nausea, vomiting, abdominal pain, constipation, dizziness, headache.
* **Serious:** Gastrointestinal bleeding, ulceration, perforation; cardiovascular thrombotic events (myocardial infarction, stroke); renal failure; hepatic failure; hypersensitivity reactions (including anaphylaxis); Stevens-Johnson syndrome, toxic epidermal necrolysis.
## Key Drug Interactions
* **Anticoagulants (e.g., warfarin):** Increased risk of bleeding.
* **Corticosteroids:** Increased risk of gastrointestinal ulceration and bleeding.
* **Selective Serotonin Reuptake Inhibitors (SSRIs):** Increased risk of gastrointestinal bleeding.
* **Diuretics, ACE inhibitors, Angiotensin II Receptor Blockers (ARBs):** May blunt diuretic effect and antihypertensive effect; increased risk of renal impairment.
* **Lithium:** Increased serum lithium levels and risk of toxicity.
* **Methotrexate:** Increased risk of methotrexate toxicity.
## Monitoring
* Monitor for signs and symptoms of gastrointestinal bleeding (e.g., melena, hematemesis).
* Monitor renal function (e.g., serum creatinine, BUN) and liver function (e.g., ALT, AST), especially in patients with pre-existing impairment or those on long-term therapy.
* Monitor blood pressure.
* Assess for signs of cardiovascular events.
* Monitor for hypersensitivity reactions.
## Clinical Pearls
* Mefenamic acid is generally intended for short-term use only.
* Advise patients to take with food or milk to minimize gastrointestinal upset.
* Discontinue immediately if signs of serious adverse effects occur.
* Consider the risks of NSAID use in patients with cardiovascular disease, renal impairment, or a history of gastrointestinal bleeding.
***
*This information is intended for clinical use and does not substitute for professional medical judgment. Always verify current prescribing information and consult relevant guidelines before making treatment decisions.*
