What is Sildenafil? Know These Things Before You Buy Sildenafil

Sildenafil Chemical Structure
Sildenafil Chemical Structure

This sildenafil guide gives us an introduction to sildenafil, including its origin, indicated uses, and sildenafil dosage. Our comprehensive sildenafil review will also discuss what available research knows about sildenafil benefits and side effects.

Sildenafil Background:

Sildenafil was originally created by Pfizer chemists in England, for the intention of treating high blood pressure (hypertension) and chest pain associated with heart disease (angina). Phase I clinical trials showed that instead of effectively benefiting angina, sildenafil is effective at promoting penile erections.

How Sildenafil Works:

Sildenafil research has shown that it is effective in ameliorating symptoms of erectile dysfunction in males. Sildenafil belongs to a class of compounds called phosphodiesterase 5 (PDE5) inhibitors. These compounds block an enzyme called phosphodiesterase type-5, which in turn increases nitric oxide’s effects in the penile tissues. As a result, Sildenafil causes an increase in blood flow to the penis, but does not directly promote sexual arousal.

Sildenafil is also used with some success in males and females to reduce pulmonary arterial high blood pressure (high blood pressure within the arteries of the lungs), improving the heart’s ability to pump sufficient blood through the lungs. In this case, Sildenafil works also via PDE5 enzyme inhibition to allow more nitric oxide to dilate the blood vessels in these arteries.

Individuals with diabetes, anti-depressant induced sexual dysfunction, and other circulatory issues often find interest in sildenafil for promoting erectile function.

Sildenafil is primarily metabolized by the liver via CPY450 (cytochrome p450) enzymes, and its primary metabolite is responsible for up to 20% of its effects.

Sildenafil Use, Effects and Side Effects:

Many people buy liquid sildenafil or Sildenafil pills (capsules or tablets). It is important to buy sildenafil that is accurate and of high potency and purity, particularly when determining the best liquid sildenafil dose. Many individuals chose to buy liquid sildenafil online, particularly in liquid form for research purposes. There are many illicit online sildenafil sources, which promote its recreational use, offer counterfeit sildenafil, or adulterate “sexual health” supplements with sildenafil.

According to available research, a commonly used effective Sildenafil dose can vary between individuals, ranging from 25mg to 100mg orally.

Sildenafil typically begins to work between 15 and 60 minutes after oral consumption. With liquid sildenafil, it is easier to absorb sildenafil faster sublingually (under the tongue). Research has shown that sildenafil is less effective when taken with food, particularly a meal higher in fat content.

Sildenafil Blood Levels
Sildenafil Absorption Time & Plasma Concentrations
Liquid Sildenafil Will Have Faster Onset Time

It is commonly known that taking sildenafil alongside other compounds or medications (particularly other blood pressure-lowering compounds) can create undesirable interactions. Reported common sildenafil side effects include too strong a drop in blood pressure, headaches, blurred vision, and digestive distress, to name a few. Some compounds can interfere with sildenafil metabolism, which will increase its plasma concentrations and pharmacologic effects to potentially dangerous levels.

It is advised to consult with a physician before taking sildenafil and to exercise caution when researching sildenafil.

Buy Sildenafil from ELV Bioscience for research or laboratory use. Our research chemicals are made in an ISO9001 cGMP facility within the United States under strict purity, potency, and quality control standards.


U.S. Patent 6,469,012

U.S. Patent 5,250,534

“Sildenafil Citrate”. The American Society of Health-System Pharmacists. Retrieved 1 December 2014.

Goldstein, I; Burnett, AL; Rosen, RC; Park, PW; Stecher, VJ (6 October 2018). “The Serendipitous Story of Sildenafil: An Unexpected Oral Therapy for Erectile Dysfunction”. Sexual Medicine Reviews. 7 (1): 115–128. doi:10.1016/j.sxmr.2018.06.005. PMID 30301707.

Laties, AM (January 2009). “Vision Disorders and Phosphodiesterase Type 5 Inhibitors: a Review of the Evidence to Date”. Drug Safety. 32 (1): 1–18. doi:10.2165/00002018-200932010-00001. PMID 19132801.

Wang, RC; Jiang, FM; Zheng, QL; Li, CT; Peng, XY; He, CY; Luo, J; Liang, ZA (March 2014). “Efficacy and Safety of Sildenafil Treatment in Pulmonary Arterial Hypertension: a Systematic Review”. Respiratory Medicine. 108 (3): 513–17. doi:10.1016/j.rmed.2014.01.003. PMID 24462476. Retrieved 5 November 2016.

Cheitlin, MD; Hutter, AM Jr; Brindis, RG; Ganz, P; Kaul, S; Russell, RO Jr; Zusman, RM (15 November 1999). “ACC/AHA Expert Consensus Document. Use of Sildenafil (Viagra) in Patients with Cardiovascular Disease”. Journal of the American College of Cardiology. 34 (6): 273–82. doi:10.1016/S0735-1097(98)00656-1. PMID 9935041.

“Viagra and Vision”. VisionWeb. 29 October 2001. Retrieved 5 November 2016.

Kloner, RA (26 December 2005). “Pharmacology and Drug Interaction Effects of the Phosphodiesterase 5 Inhibitors: Focus on α-Blocker Interactions”. The American Journal of Cardiology. 96 (12 (Suppl. 2)): 42–46. doi:10.1016/j.amjcard.2005.07.011. PMID 16387566.

Mondaini N, Ponchietti R, Muir GH, Montorsi F, Di Loro F, Lombardi G, Rizzo M (June 2003). “Sildenafil does not improve sexual function in men without erectile dysfunction but does reduce the postorgasmic refractory time”. Int. J. Impot. Res. 15 (3): 225–28. doi:10.1038/sj.ijir.3901005. PMID 12904810.

Taylor, MJ; Rudkin, L; Bullemor-Day, P; Lubin, J; Chukwujekwu, C; Hawton, K (31 May 2013). “Strategies for Managing Sexual Dysfunction Induced by Antidepressant Medication”. The Cochrane Database of Systematic Reviews (5): CD003382. doi:10.1002/14651858.CD003382.pub3. PMID 23728643.

Webb, D.J.; Freestone, S.; Allen, M.J.; Muirhead, G.J. (4 March 1999). “Sildenafil citrate and blood-pressure-lowering drugs: results of drug interaction studies with an organic nitrate and a calcium antagonist”. Am. J. Cardiol. 83 (5A): 21C–28C. doi:10.1016/S0002-9149(99)00044-2. PMID 10078539.

FDA Warns Consumers About Dangerous Ingredients in “Dietary Supplements” Promoted for Sexual Enhancement

Eardley I, Ellis P, Boolell M, Wulff M (2002). “Onset and duration of action of sildenafil for the treatment of erectile dysfunction”. Br J Clin Pharmacol. 53 Suppl 1: 61S–65S. doi:10.1046/j.0306-5251.2001.00034.x. PMC 1874251. PMID 11879261.

Nichols, DJ; Muirhead, GJ; Harness, JA (6 March 2002). “Pharmacokinetics of Sildenafil after Single Oral Doses in Healthy Male Subjects: Absolute Bioavailability, Food Effects and Dose Proportionality”. British Journal of Clinical Pharmacology. 53: 5S–12S. doi:10.1046/j.0306-5251.2001.00027.x. PMC 1874258. PMID 11879254.

Moran, Barbara (20 August 2013). “Cracking Down on Counterfeit Drugs — NOVA Next | PBS”. PBS NOVA Next. Retrieved 10 January 2017.

Deveci S, Peşkircioğlu L, Aygün C, Tekin MI, Dirim A, Ozkardeş H (2004). “Sublingual sildenafil in the treatment of erectile dysfunction: faster onset of action with less dose”. Int. J. Urol. 11 (11): 989–92. doi:10.1111/j.1442-2042.2004.00933.x. PMID 15509203.

Boolell M, Allen MJ, Ballard SA, Gepi-Attee S, Muirhead GJ, Naylor AM, Osterloh IH, Gingell C (June 1996). “Sildenafil: an orally active type 5 cyclic GMP-specific phosphodiesterase inhibitor for the treatment of penile erectile dysfunction”. Int. J. Impot. Res. 8 (2): 47–52. PMID 8858389.