Drug Category: Prostaglandin inhibitors -- In the neonate, ductal patency appears to be related to continued production of prostaglandin. This is particularly true in the premature infant; therefore, prostaglandin inhibition can affect ductal closure.
| Drug Name | Indomethacin (Indocin) -- This is the only medication indicated for PDA closure available in the United States. Prostaglandins, especially E-type prostaglandins, maintain the patency of the ductus. Thus, inhibition of prostaglandin synthesis by indomethacin results in constriction of the ductus arteriosus. |
| Adult Dose | Not indicated |
| Pediatric Dose | Many dosage regimens exist, and dose is dependent on postnatal age (PNA) at time of first dose; one example is as follows: PNA <48 hours: 0.1 mg/kg IV q12h for 3 doses PNA 2-7 days: 0.2 mg/kg IV q12h for 3 doses PNA >7 days: 0.25 mg/kg IV q12h for 3 doses |
| Contraindications | Documented hypersensitivity; GI bleeding; anuria |
| Interactions | Coadministration with aspirin increases risk of inducing serious NSAID-related adverse effects; probenecid may increase concentrations and, possibly, toxicity of NSAIDs; may decrease effects of hydralazine, captopril, and beta-blockers; may decrease diuretic effects of furosemide and thiazides; may increase PT when taking anticoagulants (watch for signs of bleeding); may increase risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently |
| Pregnancy | D - Unsafe in pregnancy |
| Precautions | Caution with intraventricular hemorrhage (particularly if active hemorrhage), renal failure, thrombocytopenia, and severe hyperbilirubinemia; increases risk of acute renal failure in patients with preexisting renal disease or compromised renal perfusion; reversible leukopenia may occur (discontinue if persistent leukopenia, granulocytopenia, or thrombocytopenia); adjust dosage interval with renal insufficiency |
