"Vision disorders and phosphodiesterase type 5 inhibitors: a review of the evidence to date".

5.1 Cardiovascular

Archived from the original on 12 October 2020. ^ "Viagra 25mg film-coated tablets Summary of Product Characteristics (SmPC)". ^ "Viagra Connect 50 mg film-coated tablets Summary of Product Characteristics (SmPC)". Archived from the original on 13 August 2020. Archived from the original on 11 October 2020.

Top What Is the Female Version of Viagra Called Related Articles

Archived from the original on 11 November 2020. ^ 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". The American Society of Health-System Pharmacists. Archived from the original on 23 April 2020.

Related support groups

PDE-5 inhibitors appear to have significant but moderate efficacy in secondary [Raynaud's phenomenon]. "Sublingual sildenafil in the treatment of erectile dysfunction: faster onset of action with less dose". "The Serendipitous Story of Sildenafil: An Unexpected Oral Therapy for Erectile Dysfunction". ^ "Drug Approval Package: Viagra (sildenafil citrate) NDA #020895". U.S. ^ "FDA Announces Revisions to Labels for Cialis, Levitra and Viagra". "Drug interactions with phosphodiesterase-5 inhibitors used for the treatment of erectile dysfunction or pulmonary hypertension".

Product	Dosage	Quantity + Bonus	Price
Viagra Soft Tabs	100mg	90 + 6 Pills	205.31€ 195.53€	Buy
Viagra Original	100mg	22 + 2 Pills	120.71€ 114.96€	Buy
Viagra Generic	200mg	90 + 6 Pills	170.79€ 162.66€	Buy
Viagra Generic	50mg	20 Pills	40.52€ 38.59€	Buy
Viagra Oral Jelly	100mg	63 + 7 Sachets	190.54€ 181.47€	Buy
Viagra Generic	50mg	180 + 8 Pills	158.82€ 151.26€	Buy
Viagra Super Active	100mg	10 Pills	28.76€ 27.39€	Buy
Viagra Generic	200mg	360 + 10 Pills	481.98€ 459.03€	Buy
Viagra Generic	25mg	360 + 10 Pills	213.68€ 203.50€	Buy
Viagra Generic	100mg	360 + 10 Pills	330.21€ 314.49€	Buy
Viagra Super Active	100mg	90 + 10 Pills	165.61€ 157.72€	Buy
Viagra Super Active	100mg	30 + 6 Pills	64.09€ 61.04€	Buy
Viagra Generic	200mg	270 + 10 Pills	379.76€ 361.68€	Buy
Viagra Professional	100mg	90 + 2 Pills	207.09€ 197.23€	Buy

"Pharmacology and drug interaction effects of the phosphodiesterase 5 inhibitors: focus on alpha-blocker interactions". Use of sildenafil (Viagra) in patients with cardiovascular disease. American College of Cardiology/American Heart Association".

How does Viagra work for ED?

"Efficacy of Sildenafil on healthy humans in high‑altitude hypoxia at rest and during exercise: A meta‑analysis". "Interventions for preventing high altitude illness: Part 1. Archived from the original on 10 June 2017. ^ "FDA Updates Labeling for Viagra, Cialis and Levitra for Rare Post-Marketing Reports of Eye Problems" (Press release). Archived from the original on 22 October 2016. Journal of the American College of Cardiology.

• Proper storage of Viagra includes keeping it in a cool, dry place.
• Never share your Viagra prescription with others.
• Viagra may cause nasal congestion in some users.
• It can improve confidence and reduce sexual anxiety.
• Viagra does not protect against sexually transmitted infections.
• Always follow the prescribed dosage for safety.

^ "Viagra (Sildenafil Citrate): Side Effects, Interactions, Warning, Dosage & Uses". Archived from the original on 12 July 2018. "Young men add Viagra to their drug arsenal". Archived from the original on 4 September 2014. "Recreational use and misuse of phosphodiesterase 5 inhibitors".

How oral medicines differ

Food and Drug Administration (FDA). Archived from the original on 31 March 2021. Archived from the original on 12 August 2025. ^ "Sildenafil Drug Usage Statistics, United States, 2014 - 2023". "Generic Viagra: Two versions of sildenafil hit the market today".

What should I tell my healthcare provider before taking sildenafil?

Archived from the original on 25 November 2018. Archived from the original on 12 February 2022. "With Viagra Now Available Over-The-Counter In The U.K., Will The U.S. "Phosphodiesterase inhibitors for erectile dysfunction buy soft viagra in patients with diabetes mellitus". "Strategies for managing sexual dysfunction induced by antidepressant medication".

Drug information

The Cochrane Database of Systematic Reviews (5) CD003382. Archived from the original on 10 October 2020. "Efficacy and safety of sildenafil treatment in pulmonary arterial hypertension: a systematic review". Archived from the original on 29 August 2021. "Raynaud's phenomenon and digital ischaemia--pharmacologic approach and alternative treatment options". Archived from the original on 21 August 2016.

• Viagra mimics the effects of natural nitric oxide in the body.
• It is important to take Viagra exactly as prescribed.
• The medication can cause headaches due to vasodilation.
• Viagra’s onset and duration vary among users.
• Exercise caution if you experience chest pain or severe dizziness.
• Always inform your doctor about any other medications taken.

"Sildenafil does not improve sexual function in men without erectile dysfunction but does reduce the postorgasmic refractory time". ^ McCambridge J, Mitcheson L, Hunt N, Winstock A (March 2006).

Brand Name	Active Ingredient	Manufacturer	Price Range ($)	Availability
Viagra	Sildenafil citrate	Pfizer	20-50 per pill	U.S. and globally
Kamagra	Sildenafil citrate	Ajanta Pharma	10-35 per pill	Online
Sildenafil CT	Sildenafil citrate	Various	15-40 per pill	Online/Pharmacies
Vivanza	Vardenafil	Menarini	25-60 per pill	Europe & Asia

"The rise of Viagra among British illicit drug users: 5-year survey data". "Does marijuana use play a role in the recreational use of sildenafil?". Archived from the original on 26 January 2013. "Sildenafil accelerates reentrainment of circadian rhythms after advancing light schedules".

Aspect	Effect	Timeframe	Notes
Erection quality	Improved	After 30 min	Enhanced rigidity
Libido	Increased (indirect)	Within 1 hour	May vary among individuals
Perception of endurance	No direct effect	-	May feel more confident
Satisfaction levels	Higher reported rates	After sex	Dependent on other factors

Proceedings of the National Academy of Sciences of the United States of America.

5.8 Effects on Bleeding

Manufacture and sale of sildenafil citrate drugs known as "generic Viagra" is common in India, where Pfizer's patent claim does not apply. Brand names include Kamagra (Ajanta Pharma), Silagra (Cipla), Edegra (Sun Pharmaceutical), Penegra (Zydus Cadila), Manly (Cooper Pharma) and Zenegra (Alkem Laboratories). Sildenafil was reclassified in New Zealand in 2014 so it could be bought over the counter from a pharmacist. It is thought that this reduced sales over the Internet and was safer as males could be referred for medical advice if appropriate. In 1999 South Korea granted two patents to Pfizer related to sildenafil.

Pulmonary hypertension

The first document guaranteed sole production and sale of the substance until 2012, while the second gave Pfizer the exclusive use to treating erectile dysfunction with sildenafil until 2014. [123] In 2011 Hanmi Pharmaceutical and CJ CheilJedang launched a suit against the exclusive use patent. The Korean Court system made a ruling against Pfizer in June 2012, allowing for the unhindered domestic production of generic prescription sildenafil. In 2012, Viagra lost its position as the top selling erectile dysfunction treatment in South Korea. This development was credited largely "due to the introduction of generic products." Generic sildenafil became publicly available in May.

Other Interactions

Sales of PalPal by Hanmi Pharmaceuticals totalled ₩22 billion or about 86% the market share of Viagra that year. [125] By 2017, there were over 50 generic sildenafil pills available. During that year Viagra sales slumped to 38% that of Palpal. There were 2,958,199 prescriptions for Sildenafil in 2016 in England, compared with 1,042,431 in 2006. In 2018, Viagra Connect, a particular formulation of Sildenafil marketed by Pfizer, became available for sale without a prescription in the UK. "Source: Roger Clemens, host of athletes pop Viagra to help onfield performance". Archived from the original on 14 August 2020. "Bears' Brandon Marshall says some NFL players use Viagra .. on the Field". Archived from the original on 5 March 2016. "Towards a decade of detecting new analogues of sildenafil, tadalafil and vardenafil in food supplements: a history, analytical aspects and health risks". "Detection of sildenafil analogues in herbal products for erectile dysfunction". Archived from the original on 4 March 2016. ^ "FDA Warns Consumers About Dangerous Ingredients in "Dietary Supplements" Promoted for Sexual Enhancement". Archived from the original on 18 January 2017. ^ "Hidden Risks of Erectile Dysfunction 'Treatments' Sold Online". Archived from the original on 23 April 2019. ^ R.

12.1 Mechanism of Action

In the US, Revatio and Viagra are marketed by Viatris after Upjohn was spun off from Pfizer. In Canada, Pfizer's patent 2,324,324 for Revatio (sildenafil used to treat pulmonary hypertension) was found invalid by the Federal Court in June 2010, on an application by Ratiopharm Inc.[106][107] On 8 November 2012, the Supreme Court of Canada ruled that Pfizer's patent 2,163,446 on Viagra was invalid from the beginning because the company did not provide full disclosure in its application. The decision, Teva Canada Ltd. v. Pfizer Canada Inc., pointed to section 27(3)(b) of The Patent Act which requires that disclosure must include sufficient information "to enable any person skilled in the art or science to which it pertains" to produce it.

Viagra (sildenafil) side effects list for healthcare professionals

It added further: "As a matter of policy and sound statutory interpretation, patentees cannot be allowed to 'game' the system in this way. This, in my view, is the key issue in this appeal. Teva Canada launched Novo-Sildenafil, a generic version of Viagra, on the day the Supreme Court of Canada released its decision. [109][110][111] To remain competitive, Pfizer then reduced the price of Viagra in Canada. [112] However, on 9 November 2012, Pfizer filed a motion for a re-hearing of the appeal in the Supreme Court of Canada,[113] on the grounds that the court accidentally exceeded its jurisdiction by voiding the patent.

Typical dosages

[114] Finally, on 22 April 2013, the Supreme Court of Canada invalidated Pfizer's patent altogether. Manufacture and sale of sildenafil citrate drugs is common in China, where Pfizer's patent claim is not widely enforced. Egypt approved Viagra for sale in 2002, but soon afterwards allowed local companies to produce generic versions of the drug, citing the interests of poor people who would not be able to afford Pfizer's price. In June 2013 Pfizer's patent on sildenafil citrate expired in some member countries of the European Union, including Austria, Denmark, France, Germany, Ireland, Italy, The Netherlands, Spain, Sweden, the United Kingdom, and Switzerland. [117][118][119] A UK patent held by Pfizer on the use of PDE5 inhibitors (see below) as treatment of impotence was invalidated in 2000 because of obviousness; this decision was upheld on appeal in 2002. Baselt, Disposition of Toxic Drugs and Chemicals in Man, 9th edition, Biomedical Publications, Seal Beach, CA, 2011, pp. Archived from the original (PDF) on 10 September 2011. "Structure of the catalytic domain of human phosphodiesterase 5 with bound drug molecules". ^ a b Webb DJ, Freestone S, Allen MJ, Muirhead GJ (March 1999). "Sildenafil citrate and blood-pressure-lowering drugs: results of drug interaction studies with an organic nitrate and a calcium antagonist". ^ Goldstein I, Lue TF, Padma-Nathan H, Rosen RC, Steers WD, Wicker PA (May 1998). "Oral sildenafil in the treatment of erectile dysfunction. Archived from the original on 14 January 2012. "Onset and duration of action of sildenafil for the treatment of erectile dysfunction".

• Viagra was the first oral medication approved for ED.
• It is sometimes used off-label for pulmonary hypertension.
• Adequate hydration is recommended when taking Viagra.
• Clinicians may adjust dosage based on individual response.
• Cialis and Levitra are alternative medications for ED.
• Follow a healthy diet and exercise to support sexual health.

^ "Scientist who developed Viagra receives knighthood in New Year's Honours". Archived from the original on 14 January 2023. "Sildenafil: from angina to erectile dysfunction to pulmonary hypertension and beyond". Archived from the original on 26 September 2008. Our clinicians regularly offer patients the opportunity to take part in trials of new drugs and treatments. Morriston Hospital in Swansea, was the first in the world to trial Viagra! ^ Boolell M, Allen MJ, Ballard SA, Gepi-Attee S, Muirhead GJ, Naylor AM, et al. "Sildenafil: an orally active type 5 cyclic GMP-specific phosphodiesterase inhibitor for the treatment of penile erectile dysfunction".