Please check your internet connection and try again.
# Mefenamic Acid (Meftal-P)
## Overview
Mefenamic acid is a nonsteroidal anti-inflammatory drug (NSAID) belonging to the fenamate class. It possesses analgesic, anti-inflammatory, and antipyretic properties.
## Primary Indications
* Short-term management of mild to moderate pain, including menstrual pain (dysmenorrhea).
* Relief of symptoms associated with rheumatoid arthritis and osteoarthritis (though less commonly used for chronic conditions compared to other NSAIDs).
## Adult Dosing
* **Pain:** 500 mg every 6 hours as needed. Dosing should not exceed 7 days.
* **Rheumatoid Arthritis/Osteoarthritis:** 750 mg three times daily.
* **Maximum Daily Dose:** 1000 mg (for pain) or 1500 mg (for chronic inflammatory conditions) is generally considered the maximum daily dose, though some sources cite higher maximums for short-term pain management. It is crucial to use the lowest effective dose for the shortest duration necessary.
## Pediatric Dosing
Mefenamic acid is generally **not recommended** for children under 14 years of age due to insufficient safety and efficacy data. Dosing for specific pediatric indications, if considered, must be determined by a specialist and based on age and weight.
## Dose Adjustments
* **Renal Impairment:** Use with caution. Dose reduction may be necessary in severe impairment. Monitor renal function closely.
* **Hepatic Impairment:** Use with caution. Dose reduction may be necessary in severe impairment. Monitor hepatic function closely.
* **Elderly:** Increased risk of adverse effects. Use the lowest effective dose and monitor closely.
## Contraindications
* Known hypersensitivity to mefenamic acid or other NSAIDs.
* History of bronchospasm, urticaria, or allergic-type reactions after aspirin or other NSAIDs.
* Perioperative pain in the setting of coronary artery bypass graft (CABG) surgery.
* Active gastrointestinal (GI) bleeding or ulceration.
* Severe renal or hepatic impairment.
* Third trimester of pregnancy.
## Adverse Effects
* **Common:** GI upset (nausea, vomiting, diarrhea, abdominal pain), dizziness, headache.
* **Serious:** GI bleeding, ulceration, perforation; renal failure; hepatic failure; cardiovascular thrombotic events (MI, stroke); hypersensitivity reactions; Stevens-Johnson syndrome/toxic epidermal necrolysis; exacerbation of asthma.
## Key Drug Interactions
* **Anticoagulants (e.g., warfarin):** Increased risk of bleeding. Monitor INR closely.
* **Corticosteroids:** Increased risk of GI ulceration and bleeding.
* **Other NSAIDs/Aspirin:** Increased risk of GI toxicity and additive effects.
* **Diuretics, ACE Inhibitors, ARBs:** May reduce antihypertensive effect and increase risk of renal impairment.
* **Lithium:** Increased lithium levels and toxicity.
* **Methotrexate:** Increased risk of methotrexate toxicity.
## Monitoring
* **Renal function:** Serum creatinine, BUN, especially in elderly patients or those with pre-existing renal disease.
* **Hepatic function:** Liver enzymes (ALT, AST), especially in patients with liver disease.
* **GI symptoms:** Monitor for signs and symptoms of bleeding (e.g., melena, hematemesis).
* **Blood pressure:** NSAIDs can increase blood pressure.
## Clinical Pearls
* Mefenamic acid is primarily indicated for short-term pain relief. Prolonged use increases the risk of serious adverse effects.
* Administer with food or milk to minimize GI upset.
* Avoid concomitant use with other NSAIDs, including aspirin (unless low-dose aspirin for cardioprotection, with caution).
* Consider gastroprotection (e.g., PPI) for patients at high risk of GI bleeding.
***
*This information is intended for healthcare professionals. Please consult the most current prescribing information and relevant clinical guidelines for complete details before making any clinical decisions.*
