Generic
Tolfenamic acid
Pharmacology
Tolfenamic acid (N-(2-methyl-3-chlorophenyl) anthranilic acid) belongs to the fenamate group and is a potent inhibitor of cyclooxygenase enzyme, thus it inhibits the synthesis of important inflammatory mediators such as thromboxane (TX) B2 and prostaglandin (PG) E2. Prostaglandins are responsible for causing swelling pain and inflammation associated with these conditions. It acts not only by inhibiting prostaglandin synthesis, but it also has direct antagonistic action on its receptors. Pharmacokinetic properties: Absorption Readily absorbed from GI tract. Peak plasma concentration: 60-90 min. Bioavailability 85%. Distribution: Protein-binding: 99% Plasma half-life 2 hours. Metabolism: Metabolised in the liver. Tolfenamic acid undergoes enterohepatic circulation. Excretion: Excreted in urine (90%) and faces.
Contraindications
The rate of absorption of Tolfenamic acid increases with Metoclopramide and Magnesium hydroxide but decreases with Aluminium hydroxide. Risk of bleeding with anticoagulants and other NSAIDS increases when use with Tolfenamic acid. It decreases antihypertensive response to loop diuretics, B-blockers and ACE Inhibitors. Co-administration increases plasma concentration of Lithium Methotrexate and cardiac glycosides. It also increases the risk of nephrotoxicity with ACE inhibitors, Ciclosporin, Tacrolimus or diuretics
Side Effects
Active peptic ulcer or bleeding in the gut. Severe heart, kidney or liver failure.
Pregnancy And Lactation
Dysuria especially in males, diarrhoea, nausea epigastric pain, vomiting, dyspepsia, erythema, headache, tremor, euphoria, fatigue, pulmonary infiltration & haematuria. Potentially fatal: Blood dyscrasias and hepatitis.
Therapeutic
Symptoms include headache, nausea, vomiting, epigastric pain. gastrointestinal bleeding, diarrhoea excitation, coma, drowsiness dizziness, tinnitus, fainting and convulsions. In cases of significant poisoning, acute renal failure and liver damage are possible. Patients should be treated symptomatically as required.
Storage Conditions
Drugs used for Rheumatoid Arthritis, Non-steroidal Anti-inflammatory Drugs (NSAIDs), Other drugs for migraine
Over The Counter Products
