Prostaglandin E1 (Vasodilator / Erectile Dysfunction / Ductus Arteriosus)

Alprostadil

Brand names: Caverject, MUSE, Viridal, Prostin VR (neonatal)

Adult dose

Dose: ED (intracavernosal): 2.5–40 mcg; ED (intraurethral MUSE): 125–1000 mcg. Ductus arteriosus: 5–10 nanogram/kg/min IV (specialist neonatal use)

Route: Intracavernosal injection or intraurethral pellet (ED); IV infusion (neonatal)

Frequency: ED: maximum 1 dose in 24 hours, max 3 times weekly

Clinical pearls

Second-line for ED after PDE5 inhibitors have failed or are contraindicated
Intracavernosal route is more effective than intraurethral (MUSE)
Priapism risk: advise patient to attend A&E if erection lasts >4 hours
In neonates, used to maintain ductus arteriosus patency in duct-dependent congenital heart disease pending surgery
Requires patient training for self-injection technique
NICE does not routinely fund ED treatments — exceptions include specific conditions (e.g., diabetes, renal failure, prostatectomy, MS)

Contraindications

Priapism or predisposition (sickle cell, leukaemia, polycythaemia)
Penile implant
Anatomical penile deformity (Peyronie's disease — caution)
Partner pregnancy (MUSE — barrier contraception required)
Hypersensitivity to prostaglandins

Side effects

Pain at injection site / urethral burning (MUSE)
Prolonged erection / priapism (seek immediate medical attention if >4 hours)
Penile fibrosis with chronic use
Hypotension (especially with urethral route)
Urethral bleeding (MUSE)
Vasovagal syncope

Interactions

Antihypertensives — additive hypotension
Anticoagulants — increased bruising at injection site
Other erectile dysfunction treatments — do not combine; risk of priapism
Heparin — infusions often contain heparin; check compatibility (neonatal use)

Monitoring

Erection quality and duration response
Injection site for fibrosis with long-term use
Blood pressure (first dose in clinic setting recommended)
Patient technique and adherence to injection protocol

Reference: BNF; NICE CKS Erectile dysfunction (2023); EAU Guidelines on Sexual and Reproductive Health (2024); https://bnf.nice.org.uk/drugs/alprostadil/. Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways