VIP is a neurotransmitter with regulatory actions on blood flow, secretion and muscle tone with intracorporal adenylate cyclase activation and smooth muscle relaxation. VIP has been shown to elevate cAMP intracellular concentrations without affecting cGMP levels. However, when VIP is given alone it may not induce erection and requires combination with phentolamine or papaverine for it to be effective (88). Common associated adverse effects were facial flushing and headache. VIP in combination with phentolamine is currently being used in the UK and Europe and is seeking regulatory approval for use in the United States.

Achieving an erection is a complicated process, requiring transmission of sensations from the genital area to the nervous system and the return of nervous impulses to the muscles and blood vessels of the penis. Anything that interferes with this interchange, such as disease or injury of the blood vessels, muscles, or nerves, can make achieving and maintaining an erection difficult. Psychological factors, such as anxiety and depression, can also interfere with erectile function. Anxiety and depression may also develop as a consequence of impotence.
A physical exam checks your total health. Examination focusing on your genitals (penis and testicles) is often done to check for ED. Based on your age and risk factors, the exam may also focus on your heart and blood system: heart, peripheral pulses and blood pressure. Based on your age and family history your doctor may do a rectal exam to check the prostate. These tests are not painful. Most patients do not need a lot of testing before starting treatment.
×