Alprostadil

Registered South African indications:

• Erectile dysfunction
• Congenital heart defects 

Contraindications

• Hypersensitivity to the active ingredient or any of its excipients
• Breastfeeding
• Sickle cell anaemia or trait
• Multiple myeloma
• Leukaemia
• Anatomical deformation of the penis
• Cavernosal fibrosis
• Peyronie's disease
• Penile implants
• Men for whom sexual activity is inadvisable or contraindicated
• Neonates with respiratory distress syndrome

Cautions

• Pregnancy
• History of bleeding tendency
• Apnoea (infants)
• Infection with blood-borne diseases
• History of transient ischaemic attacks
• Unstable cardiovascular disorder
• Cardiovascular risk factors
• Cerebrovascular risk factors
• Coronary heart disease
• Congestive cardiac failure
• Pulmonary disease
• Psychiatric disorders
• History of addiction
• Prolonged duration of treatments (infants)

Forms avail. in SA and covered in this monograph: inj, pdr

Erectile dysfunction  of neurogenic origin secondary to spinal cord injury

• Intracavernous injection (pdr): Initial: 1.25μg; Second dose 2.5μg; Third dose 5μg; Subsequent increments of 5μg until optimal dose received; Max frequency: 3 times weekly; Usual dose 5-20μg

For erectile dysfunction of vasculogenic, psychogenic, or mixed aetiology

• Intracavernous injection (pdr): Initial: 2.5μg; Second dose 5μg if partial response or 7.5μg if no response; Subsequent increments of 5-10μg until optimal dose received; Max frequency: 3 times weekly; Usual dose 5-20μg

If there is no response to the administered dose, then the next higher dose may be given within 1hr. No more than two doses may be given within a 24hr period. If there is a response after the second dose, there should be at least a 1 day interval before the next dose is given

 It is recommended that the dose administered produces a duration of the erection not exceeding 1hr

See additional prescribing points for administration directions

Paed. forms avail. in SA and covered in this monograph: inj, pdr

Maintain patent ductus arteriosus

• IV: Initial: 0.05-0,1μg/kg/min into a large vein or umbilical artery catheter; Decrease infusion to lowest effective dose when effect is achieved; Maintenance: 0.01-0.1μg/kg/min 

Cyanotic neonates with congenital heart defects may experience apnoea when treated with alprostadil, therefore it should only be used when ventilatory assistance is available

See additional prescribing points for administration directions

Pregnancy

• Not indicated for use in women
• The use of alprostadil is not indicated in women. Adverse events related to use of alprostadil have been observed in animal studies. Condom use is recommended during sexual intercourse with a pregnant woman

Breastfeeding

• Contraindicated
• The use of alprostadil is not indicated in women

Renal Impairment

• No dose adjustment recommended

Hepatic Impairment

• No dose adjustment recommended

Elderly

• No dose adjustment recommended

Porphyria Information

• Not porphyrinogenic (NP)

Drugs in Sport

• Permitted - No warnings

Central Nervous System Disorders

• Seizures
• Presyncope
• Hypoaesthesia
• Hyperaesthesia
• Cerebrovascular accident
• Hyperextension of the neck
• Hyperirritability
• Jitteriness
• Lethargy
• Microcephaly
• Rigidity

Cardiovascular Disorders

• Flushing
• Cardiac arrest
• Oedema
• Congestive cardiac failure
• Hyperaemia
• Pneumopericardium
• Second degree heart block
• Shock
• Spasm of right ventricle infundibulum
• Ventricular fibrillation
• Ventricular hypertrophy
• Bradycardia
• Hypotension
• Tachycardia
• Vascular fragility
• Supraventricular extrasystoles
• Myocardial ischaemia
• Venous haemorrhage
• Vasodilatation
• Peripheral vascular disorder
• Vein disorder

Respiratory Disorders

• Apnoea
• Bradypnoea
• Bronchial wheezing
• Hypercapnia
• Hypoplastic lungs
• Pneumothorax
• Respiratory depression
• Respiratory distress
• Tachypnoea

Gastrointestinal Disorders

• Diarrhoea
• Gastric obstruction
• Gastric mucosal hypertrophy
• Nausea
• Dry mouth
• Gastric regurgitation

Hepatobiliary Disorders

• Biliary atresia
• Hyperbilirubinaemia

Genitourinary Disorders

• Urethral haemorrhage
• Haematuria
• Dysuria
• Pollakiuria
• Micturition urgency
• Penile pain
• Peyronie's disease
• Penis disorder
• Increased erection
• Priapism
• Pelvic pain
• Testicular mass
• Spermatocele
• Testicular swelling 
• Testicular oedema
• Testicular disorder
• Scrotal pain
• Scrotal erythema
• Scrotal oedema
• Testicular pain
• Scrotal disorder
• Painful erection
• Balanitis
• Phimosis
• Erectile dysfunction
• Ejaculation disorder
• Anuria
• Haematuria
• Polycystic kidneys
• Renal failure

Endocrine and Metabolic Disorders

• Increased blood creatinine 
• Hypokalaemia
• Hyperkalaemia
• Hypoglycaemia

Musculoskeletal Disorders

• Exostosis
• Muscle spasms

Skin and Subcutaneous Tissue Disorders

• Cutaneous vasodilation
• Erythema
• Rash
• Hyperhidrosis
• Pruritus
• Injection site haematoma
• Haematoma
• Ecchymosis

Immune, Blood and Lymphatic System Disorders

• Fungal infection
• Common cold
• Disseminated intravascular coagulation
• Hypochromic anaemia
• Anaemia
• Bleeding
• Thrombocytopenia

• Coadministration with any other agents for erectile dysfunction
• Coadministration with any agents causing erection
• Sympathomimetics
• Antihypertensives
• Vasodilators
• Anticoagulants
• Platelet aggregation inhibitors

• Arterial pressure
• Respiratory rate and effort
• Heart rate
• Blood gas analysis

Administration directions

Infants

Admin. by continuous infusion through an umbilical artery catheter placed at or just above the junction of the descending aorta and the ductus arteriosus, or by intravenous drip or constant rate infusion pump.

Erectile dysfunction

Admin. by direct intracavernous injection, via 27-30 gauge needle. The site of injection is usually along the dorsolateral aspect of the proximal third of the penis. Visible veins should be avoided. Both the side of the penis that is injected and the site of injection must be alternated. Prior to the injection, the injection site must be sterilised. Inject the 1ml of diluent into the vial, and shake to dissolve the powder entirely. Adjust volume to the required dose for injection. Discard left over fluid.

Patient should be monitored for at least 3 hours or until complete detumescence has occurred in order to ensure that priapism does not occur.

Infusion solution

Dilute 1ml alprostadil sterile sodium chloride injection or dextrose containing injection. Dilute to volumes appropriate for the pump delivery system available

Alprostadil (prostaglandin E1) is produced endogenously to relax vascular smooth muscle and cause vasodilation. In adult males, the vasodilatory effects of alprostadil on the cavernosal arteries and the trabecular smooth muscle of the corpora cavernosa result in rapid arteriolar inflow and expansion of the lacunar spaces within the corpora. As the expanded corporal sinusoids are compressed against the tunica albuginea, venous outflow through the subtunical vessels is impeded and penile rigidity develops. In infants, the vasodilatory effects of alprostadil increase pulmonary or systemic blood flow.

Injection (per vial) 20μg

• Caverject (Pfizer) originator

Injection (per ml) 0.5mg

• Prostin VR (Pfizer) originator