Action/Kinetics: Alprostadil is the naturally occurring acidic lipid prostaglandin E 1. It relaxes smooth muscle of the ductus arteriosus leading to increased pulmonary blood flow with increased blood oxygenation and lower body perfusion. Clients with low pO 2 values respond best. May also cause vasodilation, inhibit platelet aggregation, and stimulate both intestinal and uterine smooth muscle. When injected intracavernosally, alprostadil relaxes the trabecular cavernous smooth muscles and causes dilation of penile arteries. This results in increased arterial blood flow to the corpus cavernosa and thus swelling and elongation of the penis. Onset, systemic: 1.5-3 hr for acyanotic congenital heart disease and 15-30 min for cyanotic congenital heart disease. Time to peak effect: 3 hr for coarctation of the aorta and 1.5 hr for interruption of aortic arch. Duration: Closure of the ductus arteriosus usually begins 1-2 hr after infusion discontinued. Alprostadil is rapidly metabolized (80% in one pass) by oxidation in the lung, and metabolites are excreted by the kidney.
Uses: Diagnosis and treatment of erectile dysfunction (male impotence) due to neurologic, vascular, psychologic, or mixed causes. Prostin VR Pediatric is used in newborns with congenital heart defects to maintain patency of the ductus arteriosus. Investigational: Diagnostic peripheral arteriography. Treat atherosclerosis, gangrene, and pain due to peripheral vascular disease.
Contraindications: Respiratory distress syndrome. Conditions that predispose to priapism: sickle cell anemia or trait, multiple myeloma, leukemia. In clients with anatomic deformation of the penis or in those with penile implants. Use in women, children, newborns, or men for whom sexual activity is not advisable or is contraindicated. Use for sexual intercourse with a pregnant woman unless a condom is used. Hyaline membrane disease.
Apnea (in 10%-12% of neonates), especially in neonates less than 2 kg at birth; bronchial wheezing, bradypnea, hypercapnia, respiratory depression. Also, in adults, respiratory infection, flu syndrome, sinusitis, rhinitis, nasal congestion, cough.
seizures hypothermia, jitteriness, lethargy,
cerebral bleeding stiffness, hyperextension of the neck, irritability.
CV: Flushing, especially after intra-arterial dosage, bradycardia, hypotension, tachycardia, edema,
cardiac arrest, CHF, shock, arrhythmias.
GI: Diarrhea, hyperbilirubinemia, gastric regurgitation.
Renal: Hematuria, anuria.
Skeletal: Cortical proliferation of long bones.
Disseminated intravascular coagulation thrombocytopenia, anemia, bleeding.
Sepsis, peritonitis hypoglycemia, hypokalemia or hyperkalemia.
Laboratory Test Alterations: Bilirubin. Glucose, serum calcium. or Potassium.
Overdose Management: Symptoms: Apnea bradycardia, flushing, hypotension, pyrexia. Treatment: Reduce rate of infusion if symptoms of hypotension or pyrexia occur; discontinue infusion if symptoms of apnea or bradycardia occur.
How Supplied: Injection: 0.5 mg/mL; Pellet: 125 mcg, 250 mcg, 500 mcg, 1000 mcg; Powder for Injection: 10 mcg/vial, 20 mcg/vial; 40 mcg/vial; Urethral Suppository: 125 mcg, 250 mcg, 500 mcg, 1000 mcg