Indomethacin

General

• Type: NSAID
• Dosage Forms: PO (Generic in 25 and 50mg tabs)
• Common Trade Names: Indocin

Adult Dosing

Preterm labor/Tocolysis

• 50-100mg loading dose, 25mg q4-6 hrs for 48 hrs

Osteoarthritis:

• 25mg PO BID-TID, max 200mg/day, give with food

Gout and Pseudogout:

• 50mg PO TID, taper dose rapidly

Ankylosing Spondylitis:

• 25mg PO bid-tid, max 200mg/day

Rheumatoid Arthritis:

• 25mg PO bid-tid, max 200mg/day

Pediatric Dosing

Patent Ductus Arteriosus:

• <48 hour old: start 0.2mg/kg IV x 1, then 0.1mg/kg q12-24h x 2
• 2-7 days old: Start 0.2mg/kg IV x 1, then 0.2mg/kg q12-24h x 2
• > 7 days old: Start 0.2mg/kg IV x 1, then 0.25mg/kg q12-24h x 2

Rheumatoid Arthritis

• 1-2mg/kg/day PO divided BID-QID, max 4mg/kg/day up to 150-200mg/day

Special Populations

• Pregnancy Rating: B
• Lactation: probably safe
• Renal Dosing
  • Adult: no adjustment
  • Pediatric: no adjustment
• Hepatic Dosing
  • Adult: not defined, caution advised if hepatic impairment
  • Pediatric: not defined, caution advised if hepatic impairment

Contraindications

• Allergy to class/drug
• ASA or NSAID-induced ashtma or urticaria
• Pregnancy 3rd trimester
• Infection, untreated (neonates)
• Active bleeding (neonates)
• Thrombocytopenia (neonates)
• Coagulation Disorder (neonates)
• Necrotizing enterocolitis (neonates)
• renal impairment, significant (neonates)
• Pulmonary atresia (neonates)
• Tetralogy of Fallot, severe (neonates)
• Aortic coarctation, severe (neonates)
• CABG surgery period use
• caution if cardiovascular disease
• caution if hypertension
• caution if CHF
• caution if fluid retention
• caution if GI bleeding or ulcer history
• caution in elderly patients
• caution if dehydration
• caution if sepsis
• caution if asthma
• caution if prolonged use

Adverse Reactions

Serious

• pulmonary hemorrhage (neonates)
• GI bleeding
• GI perforation/ulcer
• MI
• Stroke
• Thromboembolism
• hypertension
• CHF
• Renal Papillary Necrosis
• Acute Renal Failure
• Hepatotoxicity
• Steven-Johnson syndrome
• Anemia
• Thrombocytopenia, neonates
• hyponatremia (neonates)
• hyperkalemia (neonates)

Common

• dyspepsia
• nausea
• abdominal pain
• constipation
• headache
• dizziness
• rash
• ALT,AST elevation
• fluid retention
• tinnitus
• corneal deposits
• photosensitivity

Pharmacology

• Half-life: 4.5 hours, 12-21 hours in neonates
• Metabolism: Liver; CYP450, 2C9 substrate
• Excretion: urine 60%, feces 33%
• Mechanism of Action: exact mechanism unknown, inhibits cyclooxygenase, reducing prostaglandin and thromboxane synthesis

References

Authors

Babak Missaghi, Ross Donaldson, Neil Young, Daniel Ostermayer