Abstract and Introduction
Intracavernosal injections provide an effective therapy for men with erectile dysfunction who can not take oral agents or for whom oral agents are not effective. Determining the best initial dosage can be a challenge for health care providers. A literature review and 13 years of experience working with patients receiving intracavernosal injections provide the basis for the algorithm designed to provide guidance with the dosage and titration of the injection medications.Introduction
Intracavernosal injection therapy is an effective therapy for men with erectile dysfunction (ED) who can not take oral agents or for whom oral agents are not effective. Initial dosing and dosage titration is typically individualized for each man, but there are general guidelines that can be followed. In caring for men who are beginning therapy with intracavernosal penile injections, the health care clinician is faced with many choices about starting dosages and titration of medications.
Injections are given with a 1 ml syringe with 1/2 or 5/8-inch length, and a 27 to 30-gauge needle. The injection may be given anywhere from the base of the penis to two-thirds of the way down the penile shaft at the 10 o'clock and 2 o'clock locations on the upper side of the penis away from the urethra and the head of the penis (see Figure 1). Injections are rotated within that area and the side of the injection is alternated with each injection. Many factors must be considered when determining a starting dose and titrating medication for patients. The goal of this treatment is to create an erection sufficient for sexual relations, while minimizing side effects such as pain or priapism.
Figure 1. (click image to zoom)
Intracavernosal Injection Sites illustrated in shaded area.
Printer- Friendly Email ThisReferencesBaniel, J., Israilov, S., Engelstein, D., Shmueli, J., Segenreich, E., & Livne, P.M. (2000). Three-year outcome of a progressive treatment program for erectile dysfunction with intracavernous injections of vasoactive drugs. Urology, 56(4), 647-652Bennett, A.H., Carpenter, A.J., & Barada, J.H. (1991). An improved vasoactive drug combination for a pharmacological erection program. Journal of Urology, 146(6), 1564-1565Brindley, G.S. (1986). Pilot experiments on the actions of drugs injected into the human corpus cavernosum penis. British Journal of Pharmacology, 87(3), 495-500Brock, G., Tu, L.M., & Linet, O.I. (2001). Return of spontaneous erection during long-term intracavernosal alprostadil (Caverject) treatment. Urology, 57(3), 536-541Goldstein, I., Auerbach, S., Padma-Nathan, H., Rajfer, J., Fitch, W., & Schmitt, L. (2000). Axial penile rigidity as primary efficacy outcome during multi-institutional in-office dose titration clinical trials with alprostadil alfadex in patients with erectile dysfunction. Alprostadil alfadex study group. International Journal of Impotence Research, 12(4), 205-211Kuan, J.K., & Brock, G.B. (2001). Salvage of the sildenafil non-responder: The role of locally delivered therapies. Sexual Dysfunction in Medicine, 2(2), 34-39Linet, O.I., & Ogring, F.G. (1996). Efficacy and safety of intracavernosal alprostadil in men with erectile dysfunction. New England Journal of Medicine, 334(14), 873-877Montorsi, F., Salonia, A., Zanoni, M., Pompa, P., Cestari, A., Guazzoni, G., et al. (2002). Current status of local penile therapy. [review] [80 refs]. International Journal of Impotence Research, 14(Suppl. 1), S70-81Mulhall, J.P., Jahoda, A.E., Cairney, M., Goldstein, B., Leitzes, R., Woods, J., et al. (1999). The causes of patient dropout from penile self-injection therapy for impotence. Journal of Urology, 162(4), 1291-1294Pharmacia. (2002). Caverject Impulse prescribing information. Kalamazoo, MI:Pharmacia and UpJohnPorst, H., Buvat, J., Meuleman, E., Michal, V., & Wagner, G. (1998). Intracavernous alprostadil alfadex – an effective and well tolerated treatment for erectile dysfunction. Results of a long-term European study. International Journal of Impotence Research, 10(4), 225-231Richters, S., Vardi, Y., Ringel, A., Shavel, M., & Nissenkorn, I. (2001). Intra venous injections: Still the gold standard for treatment of erectile dysfunction in elderly men. International Jouranl of Impotence Research, 13, 172-175Schwarz Pharma. (2004). Edex (alpro stadil). Prescribing information. Milwaukee, WI:Schwarz PharmaSeyam, R., Mohamed, K., Akhras, A.A., & Rashwan, H. (2005). A prospective randomized study to optimize the dosage of trimix ingredients and compare its efficacy and safety with prostaglandin E1. International Journal of Impotence Research, 7, 346-353