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 management of mild to moderate pain, particularly dysmenorrhea.
## Primary Indications
* Mild to moderate pain (e.g., dental pain, post-operative pain)
* Dysmenorrhea
## Adult Dosing
* **Pain:** 500 mg every 6 hours as needed. Maximum daily dose is 1500 mg. Treatment duration should not exceed 7 days.
* **Dysmenorrhea:** 500 mg every 6 hours as needed, starting at the onset of pain and bleeding. Treatment duration should not exceed 3 days per menstrual cycle.
## Pediatric Dosing
Mefenamic acid is generally not recommended for children under 14 years of age due to limited data.
## Dose Adjustments
* **Renal Impairment:** Use with caution. Data is limited, but dose reduction may be considered in severe impairment.
* **Hepatic Impairment:** Use with caution. No specific dose adjustments are established, but monitor closely for adverse effects.
## Contraindications
* Hypersensitivity to mefenamic acid, aspirin, or other NSAIDs.
* History of NSAID-induced bronchospasm, asthma, urticaria, or allergic-type reactions.
* Perioperative pain in the setting of coronary artery bypass graft (CABG) surgery.
* Active gastrointestinal (GI) bleeding or history of recurrent GI ulceration/bleeding.
* Severe renal impairment.
* Severe hepatic impairment.
* Severe heart failure.
* Pregnancy, particularly the third trimester.
## Adverse Effects
* **Common:** Diarrhea, nausea, vomiting, abdominal pain, constipation, dyspepsia, rash.
* **Serious:** Gastrointestinal bleeding, ulceration, perforation; cardiovascular thrombotic events (myocardial infarction, stroke); renal failure; hepatic failure; hypersensitivity reactions; Stevens-Johnson syndrome/toxic epidermal necrolysis; anemia.
## Key Drug Interactions
* **Anticoagulants (e.g., warfarin):** Increased risk of bleeding.
* **Corticosteroids:** Increased risk of GI ulceration and bleeding.
* **Selective Serotonin Reuptake Inhibitors (SSRIs) / Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs):** Increased risk of GI bleeding.
* **Diuretics, ACE inhibitors, ARBs:** May reduce antihypertensive efficacy and increase risk of renal impairment.
* **Lithium:** Increased lithium levels and toxicity.
* **Methotrexate:** Increased methotrexate toxicity.
## Monitoring
* Monitor for signs and symptoms of GI bleeding (e.g., melena, hematemesis).
* Monitor renal function (BUN, creatinine) periodically, especially in patients with pre-existing renal disease or those on concomitant nephrotoxic agents.
* Monitor liver function tests (AST, ALT) periodically.
* Assess for cardiovascular risk factors and symptoms of thrombotic events.
* Monitor for signs of hypersensitivity reactions.
## Clinical Pearls
* Mefenamic acid is typically used for short-term pain management.
* It should be taken with food or milk to minimize GI upset.
* Due to the risk of diarrhea, it is often considered a second-line option for dysmenorrhea compared to other agents.
* Avoid concurrent use with other NSAIDs or aspirin to reduce the risk of adverse effects.
***
*This information is intended for healthcare professionals. Always consult the current prescribing information and institutional protocols for complete and up-to-date guidance.*
