alprostadil (intracavernosal, intraurethral)

Therapeutic Classification: erectile dysfunction agents

Pharmacologic Classification: prostaglandins

REMS

Diagnosis and treatment of erectile dysfunction.

Relaxes trabecular smooth muscle and dilates cavernosal arteries.

Therapeutic effects:

Penile erection sufficient to allow intercourse.

Absorption: Action is primarily local following intracavernosal injection; after intraurethral use, it is absorbed into the corpora cavernosa.

Distribution: Unknown.

Metabolism/Excretion: Mostly metabolized locally; any systemically absorbed alprostadil is metabolized in the liver.

Half-Life: 5–10 min.

(erection)

ROUTE	ONSET	PEAK	DURATION
Intracavernosal	5–10 min	within 20 min	1 hr
Intraurethral	5–10 min	within 20 min	0.5–1 hr

Contraindicated in:

Penile implants;
Penile abnormalities;
Balanitis;
Men for whom sexual activity is not advisable;
Conditions predisposing to priapism (e.g. sickle cell anemia/trait, multiple myeloma, leukemia);
Urethritis (suppositories).

Use Cautiously in:

Severe coagulation abnormalities or thrombocytopenia;
Patients taking anticoagulants or antihypertensive agents.

CV: hypertension, hypotension

GU: penile pain, penile edema, penile fibrosis, penile rashes, priapism

Local: bleeding, ecchymosis (injection), hematomas (injection), irritation

MS: back pain

Neuro: dizziness, headache

Resp: cough

Drug-drug:

Increased risk of bleeding at site of intracavernosal injection in patients receiving anticoagulants.
Should not be used with other vasoactive agents.
Increased risk of bleeding at injection site with anticoagulants.

Intracavernosal(Adults ): 1.25–2.5 mcg initially; dose titrated as needed. Should not be used more than 3 times/week. There should be at least 24 hr between doses. Doses >40 mcg (Edex) or >60 mcg (Caverject) should not be used.
Intraurethral(Adults ): 125–250 mcg initially; dose titrated as needed. Do not use more than 2 times in 24 hr.

Powder for injection (Caverject): 20 mcg/vial; 40 mcg/vial
Powder for injection (prefilled syringe/cartridge) (Caverject Impulse and Edex): 10 mcg; 20 mcg; 40 mcg (Edex only)
Intraurethral pellets (Muse): 250 mcg; 500 mcg; 1000 mcg

Monitor for hypotension during in-clinic dosing.

Intracavernosal Injection: Reconstitution: Reconstitute Caverject with 1 mL of bacteriostatic water with benzyl alcohol. For Caverject Impulse and Edex, follow manufacturer's instructions for reconstitution. Do not shake. Use solution immediately; do not freeze or store. Do not administer solutions that are discolored or contain precipitates. A ½-in, 27- to 30-gauge needle is used for injection. Injection must take place under sterile conditions. Injection site is usually along the dorsolateral aspect of the proximal third of the penis. Avoid visible veins. Alternate sides of the penis with each injection. Swab site with alcohol before injection. AutoInjector (PenInject 2.25) is available for self-injection.
Intraurethral: System comes with applicator, pellet, and instructions. Store unopened foil pouches in refrigerator.

Instruct patient in correct technique for use of medication.
Caution patient to report priapism (erection lasting 6 hr or longer) to health care professional immediately. Priapism is a medical emergency that can result in penile tissue damage and permanent loss of potency if not treated promptly.
- Caution patient that use of alprostadil offers no protection against sexually transmitted infections (STIs). Injection of alprostadil may cause a small amount of bleeding at injection site, increasing risk of transmission of bloodborne diseases. Advise patient to use protective measures to prevent spread of STIs, including HIV.
Intracavernosal Injection: Instruct patient on correct technique for preparation, injection, and disposal of equipment. Caution patient not to reuse or share needle with other persons. Desirable dose is determined with first injection in health care professional’s office. Advise patient not to increase dose without consulting health care professional. Injections should be administered no more than 3 times/wk, with 24 hr between injections. Advise patient to notify health care professional if nodules or hard tissue in the penis; redness, swelling, or tenderness; or curvature of the erect penis occurs. Advise patient to read Patient Information before starting therapy and with each Rx refill in case of changes.
- Emphasize the importance of follow-up exams every 3 mo to assess efficacy and safety of therapy and to adjust dose as needed.
Intraurethral: Instruct patient on proper technique for administering before self-administration. Patient should urinate before insertion. Stretch penis lengthwise and press at top and bottom. Insert the delivery device into urethra, depress button to release suppository, and hold device upright and immobile for 5 sec to help dissolve suppository. Move penis and device as a unit from side to side to help dissolve suppository and remove device. If uncomfortable or pulling sensation occurs, remove device and repeat procedure if needed. After device is withdrawn, patient should roll penis between the hands for 10 sec to further distribute suppository within walls of urethra and decrease stinging sensation. Sitting, standing, or walking for 10 min while erection is developing promotes blood flow. Patient should not exceed 2 systems in 24 hr. An erection that lasts longer than desired may be relieved by the application of an ice pack alternately to each inner thigh for a period no longer than 10 min. If erection lasts longer than 4 hrs, notify health care professional. Advise patient to read Patient Information before starting therapy and with each Rx refill in case of changes.
- Advise patient to use contraception if engaging in sexual intercourse with female of reproductive potential. Use a condom if female is pregnant; effects on the fetus are unknown.

After intracavernosal injection, an erection should occur within 5–20 min and last no longer than 1 hr.
After intraurethral administration, erection should occur within 5–10 min and last 30–60 min.

Caverject, Caverject Impulse, Edex, MUSE

section name header

Pronunciation ⬇

Classifications ⬆ ⬇

Indications ⬆ ⬇

Action ⬆ ⬇

Pharmacokinetics ⬆ ⬇

Time/Action Profile ⬆ ⬇

Contraind./Precautions ⬆ ⬇

Adv. Reactions/Side Effects ⬆ ⬇

Interactions ⬆ ⬇

Route/Dosage ⬆ ⬇

Availability ⬆ ⬇

Assessment ⬆ ⬇

Implementation ⬆ ⬇

Patient/Family Teaching ⬆ ⬇

Evaluation/Desired Outcomes ⬆ ⬇

US Brand Names ⬆