CAVERJECT Sterile Powder contains alprostadil as the naturally occurring form of prostaglandin E₁ (PGE₁) and is designated chemically as (11α,13E,15S)-11,15-dihydroxy-9-oxoprost-13-en-1-oic acid. The molecular weight is 354.49.

Alprostadil is a white to off-white crystalline powder with a melting point between 115° and 116° C. Its solubility at 35° C is 8000 micrograms per 100 milliliter double distilled water. CAVERJECT is available as a sterile freeze-dried powder for intracavernosal use in four sizes: 5, 10, 20 and 40 micro-grams per vial -When reconstituted as directed with 1 milliliter of bacteriostatic water for injection or sterile water, both preserved with benzyl alcohol 0.945% w/v, gives 1.13 milliliters of reconstituted solution. Each milliliter of CAVERJECT contains 5.4, 10.5, 20.5 or 41.1 micrograms of alprostadil depending on vial strength, 172 milligrams of lactose, 47 micrograms of sodium citrate and 8.4 milligrams of benzyl alcohol. The deliverable amount of alprostadil is 5, 10, 20 or 40 micrograms per milliliter because approximately 0.4 microgram for the 5 microgram strength, 0.5 microgram for the 10 and 20 microgram strengths and 1.1 microgram for the 40 microgram strength is lost due to adsorption to the vial and syringe. When necessary, the pH of alprostadil for injection was adjusted with hydrochloric acid and/or sodium hydroxide before lyophilization.

The structural formula of alprostadil is represented at right:

Last reviewed on RxList: 3/3/2008
This monograph has been modified to include the generic and brand name in many instances.