TOLMETIN SODIUM
Clinical safety rating: avoid
Positive evidence of fetus risks but benefits may outweigh risks in some cases
Nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis. It has anti-inflammatory, analgesic, and antipyretic effects.
| Metabolism | Primarily hepatic metabolism via cytochrome P450 enzymes, including CYP2C9 and CYP2C8, with significant first-pass metabolism. |
| Excretion | Renal excretion (~90% as unchanged drug and conjugates), with fecal excretion (~10% as metabolites) |
| Half-life | Terminal elimination half-life is approximately 4.5–6 hours (mean 5 hours); may be prolonged in elderly or patients with renal impairment |
| Protein binding | Approximately 99% bound to plasma albumin |
| Volume of Distribution | 0.1–0.2 L/kg (low Vd, indicating distribution primarily in extracellular fluid) |
| Bioavailability | Oral: 100% (well absorbed; first-pass metabolism is negligible) |
| Onset of Action | Oral: 30–60 minutes (therapeutic effect for rheumatoid arthritis may take 1–2 weeks of continuous dosing) |
| Duration of Action | 4–6 hours per dose; anti-inflammatory effect requires regular dosing for sustained benefit |
| Molecular Weight | 315.3 |
400 mg orally three times daily; maximum 1800 mg/day.
| Dosage form | TABLET |
| Renal impairment | GFR 30-59 mL/min: 50% of normal dose; GFR <30 mL/min: contraindicated. |
| Liver impairment | Child-Pugh A: no adjustment; Child-Pugh B or C: use with caution, reduce dose by 50%. |
| Pediatric use | 2 years and older: 20 mg/kg/day orally in 3-4 divided doses; maximum 30 mg/kg/day. |
| Geriatric use | Start at lowest effective dose (e.g., 400 mg once daily) and titrate cautiously; monitor renal function and gastrointestinal tolerability. |
| 1st trimester | Avoid; associated with oligohydramnios, premature ductus arteriosus closure, and neonatal renal impairment. Risk of miscarriage and cardiac defects. |
| 2nd trimester | Avoid; risk of oligohydramnios, premature ductus arteriosus closure, and neonatal renal impairment. |
| 3rd trimester | Avoid: may cause premature closure of ductus arteriosus, oligohydramnios, and neonatal renal dysfunction. |
Clinical note
ACE inhibitors and ARBs may have diminished antihypertensive effect Increases risk of serious cardiovascular thrombotic events and GI bleeding.
| Placental transfer | Crosses placenta; detected in fetal serum and amniotic fluid. |
| Breastfeeding | Tolmetin is excreted into breast milk in low concentrations. However, due to potential adverse effects on infant renal function and platelets, caution is advised. Use only if clearly needed. |
■ FDA Black Box Warning
Nonsteroidal anti-inflammatory drugs (NSAIDs) cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may increase with duration of use. Patients with cardiovascular disease or risk factors for cardiovascular disease may be at greater risk. Tolmetin is contraindicated for the treatment of peri-operative pain in the setting of coronary artery bypass graft (CABG) surgery.
| Common Effects | rheumatoid arthritis |
| Serious Effects |
Hypersensitivity to tolmetin or any NSAIDHistory of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDsActive peptic ulcer diseaseAdvanced renal diseasePerioperative pain in setting of coronary artery bypass graft (CABG) surgery
| Precautions | Cardiovascular thrombotic events; gastrointestinal bleeding, ulceration, and perforation; renal toxicity; hepatic toxicity; anaphylactoid reactions; hypertension; fluid retention; exacerbation of asthma; photosensitivity; hematologic effects; use in pregnancy (avoid in third trimester). |
Loading safety data…
| Lactation Rating | L3 (Moderately Safe) |
| Teratogenic Risk | First trimester: Risk of congenital malformations, particularly cardiac defects (OR 1.83 for NSAIDs) and gastroschisis (OR 2.5). Second trimester: Increased risk of oligohydramnios and fetal renal impairment. Third trimester: Premature closure of ductus arteriosus, persistent pulmonary hypertension, oligohydramnios, and necrotizing enterocolitis. Avoid after 30 weeks gestation. |
| Fetal Monitoring | Monitor maternal renal function, blood pressure, and signs of fluid retention. Fetal ultrasound to assess amniotic fluid volume and ductus arteriosus flow after 20 weeks. Perform fetal echocardiography if used beyond 30 weeks. Assess for oligohydramnios if used for >48 hours. |
| Fertility Effects | Potential reversible inhibition of ovulation via altered prostaglandin synthesis; may delay conception. No permanent effect on fertility. Use with caution in women attempting to conceive. |
| Food/Dietary | Take tolmetin sodium with food or milk to minimize gastrointestinal irritation. Avoid alcohol as it may increase risk of GI bleeding. No specific food restrictions. |
| Clinical Pearls | Tolmetin sodium is a nonsteroidal anti-inflammatory drug (NSAID) used for rheumatoid arthritis and osteoarthritis. Monitor renal function in elderly, diuretic users, and those with renal impairment. May cause elevated liver enzymes; discontinue if persistent abnormalities. Avoid in patients with aspirin-sensitive asthma. Use lowest effective dose for shortest duration to minimize GI and cardiovascular risks. |
| Patient Advice | Take with food or milk to reduce stomach upset. · Avoid alcohol and other NSAIDs (e.g., ibuprofen, naproxen) while taking this medication. · Report symptoms of stomach pain, black/tarry stools, or vomiting blood immediately. · Inform your doctor of any new or worsening shortness of breath, chest pain, or swelling in the legs. · May cause dizziness or drowsiness; avoid driving until you know how this drug affects you. · If you miss a dose, take it as soon as possible unless it is almost time for the next dose; do not double dose. |