Indomethacin
Brand Names: Indocin, Tivorbex
Generic Available*
Common Dosage Forms:
Capsules (Indocin)*: 25 mg, 50 mg
Capsules (Tivorbex): 20 mg, 40 mg
Capsules, sustained-release*: 75 mg
Suppository: 50 mg
Powder for Injection*: 1 mg/vial
FDA Indications/Dosages:
Moderate to severe osteoarthritis, ankylosing spondylitis, and rheumatoid arthritis (including acute flares of the chronic disease): 20-50 mg, 2-3 times a day up to 200 mg per day.
Acute painful shoulder: 75-150 mg daily in 3-4 divided doses until attack subsides.
Acute gouty arthritis: 50 mg 3 times a day until attack subsides.
Sustained-release dosage: Substitute one indomethacin SR for indomethacin 25 mg three times a day or substitute one indomethacin SR twice a day for indomethacin 50 mg three times a day. Indomethacin SR may be substituted for all the indications of indomethacin capsules except acute gouty arthritis.
Patent ductus arteriosis: See manufacturer’s package insert for dosage range of indomethacin IV.
Not recommended for use in children under 14 years of age (except indomethacin IV use in neonates).
Pharmacology/Pharmacokinetics: The mechanism of action of indomethacin is probably due to inhibition of cyclooxygenase resulting in a decreased biosynthesis of prostaglandins. Peak plasma levels after an oral dose of 25 or 50 mg capsules are reached in 2 hours. Indomethacin has a half-life of 4.5 hours. Excretion of metabolized and unchanged drug occurs in the urine and feces. 99% is bound to plasma proteins.
Drug Interactions: May increase the serum levels of lithium. May decrease the effects of beta-adrenergic blockers. May decrease the effects of loop diuretics. Do not use with other nonsteroidal anti-inflammatory agents.
Contraindications/Precautions: Contraindicated in patients hypersensitive to nonsteroidal anti-inflammatory agents. Use with caution in patients with renal impairment, hypertension, fluid retention, heart failure, bleeding disorders or a peptic ulcer, and in the elderly. Not recommended in pregnancy due to the known effects of this class of drugs on the human fetal cardiovascular system (closure of the ductus arteriosis). May mask signs of infections; use with caution in the presence of infection. NSAIDS MAY CAUSE AN INCREASED RISK OF SERIOUS CARDIOVASCULAR THROMBOTIC EVENTS, MYOCARDIAL INFARCTION, AND STROKE. NSAIDS HAVE BEEN INVOLVED IN RARE CASES OF GI BLEEDING INCIDENTS. No Pregnancy Category Established.
Adverse Effects: GI cramping, indigestion, constipation, drowsiness, dizziness, somnolence, depression and fatigue, tinnitus, headache, diarrhea, nausea, and vomiting.
Patient Consultation:
Compliance with therapy is essential, may require up to 2 weeks to see noticeable improvement in arthritic conditions.
Take with food, after meals, or with antacids to reduce GI upset.
Concurrent ingestion of alcohol may increase ulcerogenic effect.
Avoid aspirin or products containing aspirin without first consulting physician.
May cause drowsiness. Use caution while operating machinery or when mental alertness is required.
Store in a cool, dry place away from sunlight and children.
If a dose is missed, take it as soon as possible. If it is closer to the time of your next dose than the dose you missed, skip the missed dose, and return to your dosing schedule.
Contact a physician if the above side effects are severe or persistent.
Shake suspension well before using. May be stored at room temperature.
