Effects of Viagra on Erectile Response

Viagra (sildenafil citrate), an oral therapy for erectile dysfunction, is the citrate salt of sildenafil, a selective inhibitor of cyclic guanosine monophosphate

(cGMP)-specific phosphodiesterase type 5 (PDE5).

Sildenafil citrate is designated chemically as 1-[[3-(6,7-dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-5-yl)-4-ethoxyphenyl]sulfonyl]-4-methylpiperazine

citrate and has the following structural formula:   Sildenafil citrate is a white to off-white crystalline powder with a solubility of 3.5 mg/mL in water and a molecular weight of 666.7.onlinepharmacy

Viagra is formulated as blue, film-coated rounded-diamond-shaped tablets equivalent to 25 mg, 50 mg and 100 mg of sildenafil for oral administration. In addition to

the active ingredient, sildenafil citrate, each tablet contains the following inactive ingredients: microcrystalline cellulose, anhydrous dibasic calcium phosphate,

croscarmellose sodium, magnesium stearate, hypromellose, titanium dioxide, lactose, triacetin, and FD & C Blue #2 aluminum lake.   Viagra – Clinical Pharmacolog

The physiologic mechanism of erection of the penis involves release of nitric oxide (NO) in the corpus cavernosum during sexual stimulation. NO then activates the

enzyme guanylate cyclase, which results in increased levels of cyclic guanosine monophosphate (cGMP), producing smooth muscle relaxation in the corpus cavernosum and

allowing inflow of blood.

Sildenafil enhances the effect of NO by inhibiting phosphodiesterase type 5 (PDE5), which is responsible for degradation of cGMP in the corpus cavernosum. whatisviagraSildenafil

has no direct relaxant effect on isolated human corpus cavernosum. When sexual stimulation causes local release of NO, inhibition of PDE5 by sildenafil causes

increased levels of cGMP in the corpus cavernosum, resulting in smooth muscle relaxation and inflow of blood to the corpus cavernosum. Sildenafil at recommended doses

has no effect in the absence of sexual stimulation.

Most studies assessed the efficacy of Viagra approximately 60 minutes post dose. The erectile response, as assessed by RigiScan?,

generally increased with increasing sildenafil dose and plasma concentration. The time course of effect was examined in one study, showing an effect for up to 4 hours

but the response was diminished compared to 2 hours.

Viagra (sildenafil) is used for the treatment of erectile dysfunction

Viagra (sildenafil) is used for the treatment of erectile dysfunction. It is a phosphodiesterase-5 (PDE5) inhibitor. Side effects of Viagra (sildenafil) include warmth or redness in the face, neck, or chest; stuffy nose; headaches, stomach pain, nausea, diarrhea, and an inability to differentiate between the colors green and blue. Loss of hearing, ringing in the ears and dizziness are other potential side effects.

The recommended dose of Viagra is 25-100 mg taken 30 minutes to 4 hours before sexual activity. Viagra increases the effects of blood pressure lowering medications. It also increases the blood pressure lowering effects of nitrates (for example, isosorbide dinitrate) that are used primarily for treating angina. Patients taking nitrates should not receive Viagra.canadianpharmacy Viagra should not be combined with Revatio or other PDE5 inhibitors (for example, Levitra [vardenafil], Cialis [tadalafil]). Tagamet (cimetidine), erythromycin, ketoconazole, Sporanox (itraconazole), and Posicor (mibefradil) can cause marked increases in the amount of Viagra in the body. Patients taking these medications should be observed carefully if Viagra is used.

Our Viagra Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.   This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. VIAGRA (sildenafil citrate), an oral therapy for erectile dysfunction, is the citrate salt of sildenafil, a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5).

Sildenafil citrate is designated chemically as 1-[[3-(6,7-dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo[4,3d]pyrimidin-5-yl)-4-ethoxyphenyl]sulfonyl]-4-methylpiperazine citrate and has the following structural formula:viagraforwomen

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

During sexual activity, if you become dizzy or nauseated, or have pain, numbness, or tingling in your chest, arms, neck, or jaw, stop and call your doctor right away. You could be having a serious side effect of sildenafil.