Levitra online

Viagra prevent the breakdown of nitric oxide, a chemical messenger that promotes relaxation and opening of the blood vessels that supply erectile tissue in the penis. Under the influence of nitric oxide, these vessels expand and stay dilated. Increased blood flow makes erectile tissue swell and compress the veins that carry blood out of the penis, resulting in a full erection.

PDE-5 inhibitors do not automatically trigger erections. Sexual stimulation also is needed to start the whole process. The medications enable a more complete response to sexual stimulation.

 Many clinical trials have shown that PDE-5 inhibitors improve erectile function regardless of the underlying cause or causes. Viagra  increase the number and quality of erections and sexual experiences in men with erectile dysfunction due to arteriosclerosis, diabetes, spinal cord injury, depression or the aftereffects of prostate cancer surgery. 

The drugs have slightly different chemical compositions that affect how quickly they work and wear off. Other distinctions — for example, which drug may be best for men of different ages or with different medical conditions — aren’t known. No study has directly compared these three medications. Several factors may affect your choice of medication, including how well your body responds to one drug over another and how long you want the effects of each dose to last. Talk to your doctor about your options and personal preferences to help decide which one of these medications might work for you.

 Although these medications can help many people, not all men can safely take them. PDE-5 inhibitors may worsen certain medical conditions and interact with a number of drugs. Erectile dysfunction medications are dangerous when used with nitrate medications, such as nitroglycerin (Nitro-Dur, others), often prescribed to prevent or treat acute angina (chest pain due to coronary artery disease). Both types of medication dilate blood vessels, and their combined effects can cause dizziness, low blood pressure and loss of consciousness. In rare cases, men using PDE-5 inhibitors have suffered permanent, total vision loss due to nonarteritic anterior ischemic optic neuropathy (NAION). Because NAION and erectile dysfunction share many of the same risk factors, it’s unclear whether the drug or an underlying condition is responsible. If you’re considering an erectile dysfunction drug but have a retinal disorder, such as diabetic retinopathy, see your eye doctor first.

BACKGROUND: Viagra may be used medically to treat erectile dysfunction or used recreationally to enhance sexual performance. Little is known about predictors of Viagra use among HIV-seropositive (HIV+) men who have sex with men (MSM), whether it is used with contraindicated substances, and the relationship with sexual risk. METHODS: A community-based sample of 1168 HIV+ MSM (55% men of color) from two large cities in the U.S. completed an A-CASI interview about their sexual practices and substance use in the past 3 months. In univariate analyses, Viagra use was associated with demographics, health status, substance use, and sexual risk. Logistic regression was conducted to predict Viagra use, with significant univariate predictors entered. RESULTS: One in eight men (12%) used Viagra, and many reported using contraindicated illicit substances (inhalants=53%) or HIV medications (indinavir=19%). In logistic regression, predictors of Viagra use were being older (OR, 1.06, 95% CI, 1.03-1.09), having education beyond high school (OR, 2.25, 95% CI, 1.16-4.36), taking HIV medications (OR, 1.98, 95% CI, 1.05-3.72), using any illicit substance (OR, 1.92, 95% CI, 1.16-3.18), using ketamine (OR, 2.82, 95% CI, 1.09-7.32), engaging in unprotected oral insertive intercourse (UOI) with HIV-negative or unknown serostatus non-main partners (OR, 1.88, 95% CI, 1.15-3.09), and engaging in unprotected anal insertive intercourse (UAI) with HIV-positive non-main partners (OR, 2.39, 95% CI, 1.33-4.31). CONCLUSIONS: Many HIV+ MSM used Viagra, particularly substance using men. Use of contraindicated illicit and prescribed medications was common. Viagra use was associated with UOI (but not UAI) with non-main partners who might be at risk of contracting HIV. With HIV+ non-main partners, Viagra users were more likely to engage in UAI. Providers should educate HIV+ Viagra users about potential interactions with other substances and provide counseling to reduce HIV and STD risks. Publication Types:

• Meeting Abstracts

Keywords:

• Acquired Immunodeficiency Syndrome
• HIV Infections
• HIV Seropositivity
• Humans
• Male
• Piperazines
• Sexual Behavior
• Substance-Related Disorders
• United States
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