Treatment Options

Oral medications:

• Phosphodiesterase Type 5 (PDE5) Inhibitors
  • Viagra (Sildenafil) – Pfizer
  • Levitra (Vardenafil) – Bayer/Glaxo-Smith Kline
  • Cialis (Tadalafil) – Icos/Lilly
• Unlike the other treatment options described below, PDE5 inhibitors do not cause an immediate erection. These pills work by blocking a chemical in the penis that normally causes the erection to subside. In this way, PDE5 inhibitors enhance the erection as it begins to occur. The pills are taken as needed and are effective only when a man is sexually stimulated. Viagra and Levitra should be taken on an empty stomach (to allow for maximum absorption) and will typically be effective 30 – 45 minutes later. Cialis can be taken regardless of meals and studies have reported effectiveness within 30-45 minutes of ingestion. Viagra and Levitra will typically stay in your system for about 4-6 hours whereas Cialis is reported to be effective for up to 24-36 hours after ingestion.
• As with most medications, PDE5 inhibitors can interact with other medications and cause detrimental effects. Nitrate medications, such as nitroglycerin and Isosorbide dinitrate (Isordil) as well as the recreational drug Amyl nitrate, cannot be taken at any time if you are using PDE5 inhibitors. For patients considering using Cialis, it is important to avoid nitrate medications for up to 48 hours after ingesting Cialis. Alpha – blocking medications, another class of medications, can also cause drops in blood pressure if taken with PDE5 inhibitors. Alpha blocking agents are commonly used to control blood pressure as well as to treat symptoms of prostate enlargement. Alpha- blockers include Hytrin (Terazosin), Cardura (Doxazosin), and Flomax (Tamsulosin). For patients taking Viagra you must avoid taking alpha- blockers within 4 hours of ingesting Viagra. For patients taking Cialis, you can only take Flomax at a dose of 0.4 mg daily. Use of Cialis with Hytrin or Cardura or a higher dose of Flomax is prohibited. Use of Levitra with any type of alpha-blocker is prohibited.
• PDE5 inhibitors have been shown to be effective for treatment of erectile dysfunction. Viagra has been available since 1998 and experience with this medication has shown approximately 70% of patients will have a positive response to Viagra. Studies using Levitra and Cialis have shown similar results with regard to effectiveness although they have only been approved since 2003.
• Side effects are similar for all three types of PDE5 inhibitors with the most common being headaches, facial flushing, nasal congestion, indigestion and visual disturbances. Studies using Cialis have also reported back pain and muscle aches in a small percentage of patients, which have not been reported to occur with Viagra or Levitra.