Drug Interactions with Sildenafil Citrate Medication

American College of Cardiology/American Heart Association". Journal of the American College of Cardiology. ^ "Viagra (Sildenafil Citrate): Side weekend viagra 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". Archived from the original on 21 August 2016. "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). "The rise of Viagra among British illicit drug users: 5-year survey data".

• Use of generic Viagra is contraindicated for those with heart conditions.
• Regular medical check-ups are advised while using sildenafil.
• The medication may cause priapism, an erection lasting over 4 hours.
• Alcohol intake can impair the effectiveness of the drug.

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

What happens if I overdose?

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.

The Bottom Line

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". ^ "FDA Warns Consumers About Dangerous Ingredients in "Dietary Supplements" Promoted for Sexual Enhancement".

Product	Dosage	Quantity + Bonus	Price
Viagra Professional	100mg	180 + 4 Pills	337.30€ 321.24€	Buy
Viagra Original	100mg	12 Pills	72.54€ 69.09€	Buy
Viagra Original	100mg	92 + 4 Pills	362.88€ 345.60€	Buy
Viagra Soft Tabs	100mg	60 + 6 Pills	152.94€ 145.66€	Buy
Viagra Oral Jelly	100mg	110 + 9 Sachets	284.63€ 271.08€	Buy
Viagra Generic	100mg	360 + 10 Pills	330.21€ 314.49€	Buy
Viagra Original	100mg	64 + 4 Pills	264.15€ 251.57€	Buy
Viagra Generic	50mg	90 + 6 Pills	107.37€ 102.26€	Buy
Viagra Original	100mg	120 + 8 Pills	470.39€ 447.99€	Buy
Viagra Generic	150mg	10 Pills	36.73€ 34.98€	Buy
Viagra Generic	200mg	30 + 2 Pills	83.07€ 79.11€	Buy
Viagra Generic	150mg	120 + 8 Pills	177.58€ 169.12€	Buy
Viagra Generic	100mg	20 Pills	45.58€ 43.41€	Buy

Archived from the original on 18 January 2017.

Adverse effects

[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.

Marketing and sales

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. ^ "Hidden Risks of Erectile Dysfunction 'Treatments' Sold Online". Archived from the original on 23 April 2019.

Related/similar drugs

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.

Sildenafil Oral Film for ED

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. ^ R. Baselt, Disposition of Toxic Drugs and Chemicals in Man, 9th edition, Biomedical Publications, Seal Beach, CA, 2011, pp.

Are there any differences between Viagra and 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 in viagra 100mg patients with diabetes mellitus". "Strategies for managing sexual dysfunction induced by antidepressant medication".

Drug details

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 (PDF) on 10 September 2011. "Structure of the catalytic domain of human viagra alternative uk phosphodiesterase 5 with bound drug molecules". ^ a b Webb DJ, Freestone S, Allen MJ, Muirhead GJ (March 1999).

Parameter	Value	Notes
Onset of Action	30-60 minutes	Typically reaches peak plasma levels in this time
Duration	Up to 4-6 hours	Effects can last for several hours
Bioavailability	~40%	Oral bioavailability varies with food intake
Half-life	3-5 hours	Half-life determines how long the drug stays active

"Sildenafil citrate and blood-pressure-lowering drugs: results of drug interaction studies with an organic nitrate and a calcium antagonist".

Form	Strength	Packaging Options	Brand Examples	Notes
Tablet	50 mg	Blister packs of 4, 10, 20 tablets	Viagra, Kamagra, Sildenafil	Standard oral tablet, prescription or OTC
Chewable Tablet	50 mg	Bottles of 20 tablets	Viagra Chew, Sildenafil Melt	Faster absorption, easier to take
Dispersible Tablet	50 mg	Disintegration strips	Sildenafil Disper, Generic Quad	Dissolves in water, convenient

^ 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.

Frequently asked questions

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.

What are the most common side effects of sildenafil?

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. "Onset and duration of action of sildenafil for the treatment of erectile dysfunction". ^ "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!

Storage Aspect	Recommendation	Notes
Temperature	Store at 20-25°C (68-77°F)	Keep away from heat and moisture
Light Exposure	Protect from light	In original packaging
Humidity	Keep dry	Avoid bathroom storage

^ Boolell M, Allen MJ, Ballard SA, Gepi-Attee S, Muirhead GJ, Naylor AM, et al.

• Sildenafil citrate works by blocking PDE5 enzymes.
• It is not an aphrodisiac; arousal is necessary for effectiveness.
• Consult a doctor before use, especially if on other medications.
• Common side effects include headaches, flushing, and dizziness.

"Sildenafil: an orally active type 5 cyclic GMP-specific phosphodiesterase inhibitor for the treatment of penile erectile dysfunction". "Sildenafil (Viagra), a potent and selective inhibitor of Type 5 cGMP phosphodiesterase with utility for the treatment of male erectile dysfunction". "Drug repositioning: identifying and developing new uses for existing drugs". Archived from the original on 22 April 2019. Archived from the original on 10 June 2019. "Health situation in former communist bloc is dire, says Unicef". Archived from the original on 1 November 2012. ^ Gurevich M, Cormier N, Leedham U, Brown-Bowers A (August 2018). Sexuopharmaceutical use by men as prevention and proficiency".

• Sildenafil improves erectile function when sexual stimulation occurs.
• It is not effective as a cure for ED, only as a treatment.
• Ensure privacy and a proper environment for medication use.
• Keep out of reach of children for safety reasons.

"Spreading the Word, but What Word is That? Viagra and Male Sexuality in Popular Culture". "A new view of women's sexual problems: Why new? Archived from the original on 3 January 2009. Archived from the original on 12 October 2008. "Sales of Impotence Drugs Fall, Defying Expectations". Archived from the original on 11 October 2007.

Further information

"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.

Patient resources

"Vision disorders and phosphodiesterase type 5 inhibitors: a review of the evidence to date". ^ "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". "Pharmacology and drug interaction effects of the phosphodiesterase 5 inhibitors: focus on alpha-blocker interactions". Use of sildenafil (Viagra) in patients with cardiovascular disease. ^ "Pfizer Courting More Controversy with Viagra 'Advergaming'". Archived from the original on 19 December 2019. Archived from the original on 6 May 2018. Archived from the original on 9 January 2009. Archived from the original on 22 February 2021. ^ a b "Viagra now available over the counter without prescription in the UK". Archived from the original on 26 March 2021.