Alprostadil

Alprostadil is a prescription medication used to treat certain types of erectile dysfunction.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Erectile Dysfunction

Used to facilitate attainment of a sexually functional erection in males with erectile dysfunction (ED, impotence).98 110 b

Second-line therapy for treatment of ED in patients not responding to psychotherapy/behavioral therapy, vacuum constriction devices, and/or oral, selective phosphodiesterase (PDE) type 5 inhibitors (e.g., sildenafil, tadalafil, vardenafil)19 23 65 112 s t u v and in whom attempts at identifying and modifying any drug-related (e.g., certain antihypertensive agents) or other potentially reversible medical causes of ED have proved inadequate.2 19 23 65 112

Selective oral PDE type 5 inhibitor therapy preferred as first-line treatment of ED unless contraindicated.112

Intraurethral therapy generally preferred over intracavernosal vasoactive therapy because it is less invasive; however intracavernosal therapy is most effective nonsurgical treatment for ED.112

Consider intraurethral therapy for patients with inadequate responses to or who are not candidates for selective oral PDE type 5 inhibitor therapy.112

Effective in patients with organic (neurogenic and/or mild to moderate vasculogenic) ED or with psychogenic ED.19 20 24 25 27 34 36 41 45 46 64 67 71

Not recommended for simply enhancing erections in men who are not impotent† because of GU risks.64 (See Priapism and also GU Effects, under Cautions.)

Manufacturers state that safety and efficacy of alprostadil in combination with other vasoactive therapy for erectile dysfunction not established and currently not recommended.64 101 b However, American Urological Association (AUA) and other clinicians state that combination therapy with other intracavernosal vasoactive agents increased efficacy and decreased adverse effects relative to alprostadil alone.9 10 11 12 14 15 17 18 21 65 71 90 91 y z Combined therapy with intraurethral alprostadil and vacuum constriction device or oral selective PDE type 5 inhibitor increased efficacy relative to alprostadil alone.112

Adjunct to other vascular testing (e.g., duplex ultrasonography, cavernosometry/cavernosography, angiography, radioisotope penogram) in differential diagnosis of ED and evaluation of hemodynamic status of erectile tissue.5 15 16 17 21 24 27 28 65 66 67 110 b

Ductus Arteriosus-dependent Congenital Heart Disease

Palliative treatment in maintaining patency of ductus arteriosus in neonates with various ductal-dependent congenital heart defects (e.g., pulmonary atresia, pulmonary stenosis, tricuspid atresia, tetralogy of Fallot, interruption of aortic arch, coarctation of the aorta, transposition of great vessels).1 3 29 42 43 44 47 51 56 57 60

Used to provide adequate circulation and oxygenation and prevent or correct resultant acidemia until corrective or palliative surgery can be performed.1 3 42 43 44 47 49 51 52 53 54 55 56 60

Do not use in neonates with respiratory distress syndrome.1 4 42 49 64 (See Respiratory Distress Syndrome under Cautions.)

Ductus Arteriosus-dependent Congenital Heart Disease

• Dilates constricted ductus arteriosus in neonates with cyanotic congenital heart disease.1 3 43 56 58

• In neonates with restricted pulmonary blood flow, increases pulmonary blood flow through combined maintenance of patency of ductus arteriosus and dilation of pulmonary vascular bed.43 44 55 56 58 60 70 Temporarily increases arterial oxygen partial pressure (PaO2) and oxygen saturation.1 3 43 56 58

• In neonates with restricted systemic blood flow, prevents or corrects acidemia and increases cardiac output, systemic BP, femoral pulse volume, and renal blood flow and function (urine production).1 3 29 43 44 51 56 57 60

• In neonates with coarctation of aorta, decreases gradient of descending to ascending aortic BP.1 3 29 43 44 51 56 57 60

• In neonates with interruption of aortic arch, decreases gradient of pulmonary artery to descending aortic BP.1 3 29 43 44 51 56 57 60

Erectile Dysfunction

• Interacts with specific membrane-bound receptors that stimulate adenylate cyclase and elevates intracellular concentrations of cyclic adenosine-3’,5’-monophosphate (AMP), leading to activation of protein kinase and resultant smooth muscle relaxation.6 8 12 97 z

• Induces erection by relaxing trabecular smooth muscle and dilating cavernosal arteries and their branches (i.e., the helicine arterioles of the penis).2 11 15 19 20 21 24 27 28 34 46 64 65 71 98 101 102

• Increases arterial inflow velocity and venous outflow resistance resulting in penile blood engorgement and erection.15 18 85 98 110

• Drug may enhance actions of nonadrenergic, noncholinergic, vasodilatory neurotransmitters (e.g., nitric oxide, neuropeptide Y, calcitonin gene-related peptide, vasoactive intestinal polypeptide).6 8 12 20 21 33 46 62

Erectile Dysfunction

• Importance of providing patient a copy of manufacturer’s patient information.5 83 98 100 101 112

• Importance of informing clinician of history of syncope prior to treatment initiation with intraurethral suppository.100

• Importance of understanding proper storage, preparation, and administration techniques, including precautions and proper disposal of used needles, injection devices, syringes and unused reconstituted drug solutions.5 10 22 34 67 69 71 83 98 100 101 110 112 d

• Importance of not storing vials or injection devices in checked airline baggage (storage in passenger compartment permitted) or closed automobile.64 111 e r Importance of avoiding freezing or exposure to temperatures >25°C.64 111 e

• Importance of contacting a clinician if needle breaks during penile injection.e i r

• Potential for transmission of sexually transmitted diseases or blood-borne diseases and need to use protective measures to guard against such transmission.110 (See Hematologic Effects under Cautions.)

• With intraurethral suppository, importance of using a condom when engaging in sexual intercourse with a pregnant woman.98 100 104 (See Contraindications under Cautions.)

• Importance of contacting clinician regularly for assessment of therapeutic benefit, need for possible dosage adjustment, and of potential adverse effects.34 41 89 101 110

• Importance of seeking immediate medical attention if erection persists >4 hours.34 78 79 89 98 100 110 112 113 (See Priapism under Cautions.)

• Importance of informing clinician of penile pain that develops or intensifies during intracavernosal therapy. 110

• Importance of informing clinician of nodules or hard areas in penis, any sign of infection (e.g., penile erythema, swelling, tenderness) or unusual curvature.110

• Possible dizziness, hypotension, or syncope with intraurethral suppository; use caution when driving or operating machinery.98 Importance of lying down and immediately raising legs if light-headed feeling, dizziness, feeling of faintness, or rapid pulse experienced.100 Importance of informing a clinician if such symptoms persist.100

• Importance of informing clinician of existing or contemplated concomitant therapy (e.g., agents interfering with blood clotting, antihypertensive agents), including prescription and OTC drugs, as well as any concomitant illnesses (e.g., conditions interfering with blood clotting).98 110 d r

• Importance of informing patients of other important precautionary information.d (See Cautions.)

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Alprostadil injection USP is indicated for palliative, not definitive, therapy to temporarily maintain the patency of the ductus arteriosus until corrective or palliative surgery can be performed in neonates who have congenital heart defects and who depend upon the patent ductus for survival. Such congenital heart defects include pulmonary atresia, pulmonary stenosis, tricuspid atresia, tetralogy of Fallot, interruption of the aortic arch, coarctation of the aorta, or transposition of the great vessels with or without other defects.

In infants with restricted pulmonary blood flow, the increase in blood oxygenation is inversely proportional to pretreatment pO2 values; that is, patients with low pO2 values respond best, and patients with pO2 values of 40 torr or more usually have little response.

Alprostadil injection USP should be administered only by trained personnel in facilities that provide pediatric intensive care.

Ductus arteriosus will begin to close within 1 to 2 hours after drug is stopped; Erectile dysfunction: Intended duration <1 hour

Half-Life Elimination

30 seconds to 10 minutes

Protein Binding

Plasma: 81% to albumin

Pulmonary disease: May have reduced capacity to clear the drug.

Apnea is experienced by about 10% to 12% of neonates with congenital heart defects treated with alprostadil pediatric sterile solution. Apnea is most often seen in neonates weighing less than 2 kg at birth and usually appears during the first hour of drug infusion. Therefore, monitor respiratory status throughout treatment, and use alprostadil pediatric injection where ventilatory assistance is immediately available.

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Have patient report immediately to prescriber severe penile pain, redness, swelling, or curving; injection site irritation; angina; tachycardia; severe dizziness; passing out; severe headache; shortness of breath; bruising; bleeding; or priapism (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.