Open Surveys

Archived from the original on 9 September 2017.

Overdose/Missed Dose

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

Information leaflet

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). ^ "Viagra to go generic in 2017 according to Pfizer agreement". Archived from the original on 1 December 2017. "Sex, Drugs and That Little Blue Pill". Archived from the original on 6 December 2017. "Why Pfizer Is About to Slash Viagra's Price in Half". Archived from the original on 7 December 2017. "Pfizer to lose patent of drug Viagra, Indian companies gear up with copycat versions: Pfizer's patent for the formulation of Viagra, used to treat impotence in men, ends in the US in 2020". Archived from the original on 17 April 2021. ^ "Set to conquer US, Indian 'Viagras' may give Pfizer a hard Time". Archived from the original on 22 December 2020. ^ a b "Pfizer Settles Viagra® Patent Litigation With Teva". "Lockout Supplements Issues Voluntary Nationwide Recall viagra cream of Boner Bears Chocolate Syrup Due to Undeclared Sildenafil". Archived from the original on 19 November 2016. "Counterfeit Viagra, Cialis, Levitra: The Ultimate Guide". Archived from the original on 10 January 2017. "Online pharmacies suspected of counterfeit drug sales". ^ "Erectile Dysfunction Medication the Most Seized Drug During Global Crackdown, Interpol Says". ^ "Global illicit medicines targeted by INTERPOL operation". Archived from the original on 10 December 2023. ^ "Israeli-made AI exposes international fake Viagra network". ^ "Counterfeit Viagra Pills, Footwear, Belts, Car Emblems and Headphones Worth over $32 Million Seized at the LA/Long Beach Seaport U.S. Customs and Border Protection". Archived from the original on 12 October 2013. "Yes, There Is a Way to Get Generic Viagra". Archived from the original on 2 May 2016. "Pfizer Wins Viagra Patent Infringement Case Against Teva Pharmaceuticals". Archived from the original on 11 January 2015. ^ "Pfizer Completes Transaction to Combine Its Upjohn Business with Mylan".

Retrieved 17 June 2024 – via Business Wire. Archived from the original on 17 June 2024. "Viagra patent expires in June, says Brazilian court". Archived from the original on 17 April 2012. ^ "Revatio patent ruled invalid for lack of sound prediction and obviousness". Archived from the original on 3 March 2016. {{cite web}}: CS1 maint: deprecated archival service (link) ^ Teva Canada Ltd. v. Pfizer Canada Inc., 2012 SCC 60 at par. "Supreme Court ruling could lead to cheaper versions of Viagra". Archived from the original on 10 March 2013. "Canadian Supreme court rules Viagra patent invalid". Archived from the original on 11 November 2012. ^ "Viagra patent tossed out by Supreme Court: Decision allows generic versions of drug to be produced". Archived from the original on 18 September 2013. ^ "Pfizer Canada drops Viagra price after generic versions get Supreme Court green light". Archived from the original on 30 November 2012. Archived from the original on 27 December 2013.

Product Specification

"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". ^ "Scientist who developed Viagra receives knighthood in New Year's Honours". Archived from the original on 14 January 2023.

What should I tell my healthcare provider before taking sildenafil?

"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. "In rare move, Pfizer asks Supreme Court to reconsider ruling that killed Viagra patent". Archived from the original on 5 February 2013. "The Supreme Court of Canada holds Pfizer's Viagra patent invalid". Archived from the original on 20 May 2013.

• The 25 mg tablet is a tool, not a solution, for relationship issues related to ED.
• PDE5 inhibition leads to increased cyclic GMP, causing smooth muscle relaxation.
• Generic sildenafil must meet the same FDA standards for safety and efficacy.
• Taking with a high-fat meal can delay Tmax (time to peak concentration) by one hour.
• Men with cardiovascular disease need stress testing before sexual activity.
• The medication is metabolized primarily by the liver enzyme CYP3A4.
• Inhibitors of CYP3A4 (like some HIV drugs) can increase sildenafil levels.
• Inducers of CYP3A4 (like rifampin) can decrease sildenafil levels.
• Non-arteritic anterior ischemic optic neuropathy (NAION) is a potential risk.
• Patients with a history of NAION in one eye are at increased risk in the other.
• A urologist or primary care physician can provide a prescription.

^ "Actavis Launches Generic Viagra in Europe as Patents Expire". Archived from the original on 29 October 2013. "What Will Happen When Viagra Goes Generic?". Archived from the original on 23 April 2011. ^ "Is Viagra about to lose its pulling power in the UK?". Archived from the original on 30 October 2013. Archived from the original on 22 August 2009.

Archived from the original on 25 June 2007. "Viagra from the pharmacist: insight from reclassification in New Zealand". Archived from the original on 17 May 2021.

Select a medication above to begin.

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. Archived from the original on 8 December 2013. "The coming generics threat to Pfizer's Viagra brand just got scarier". ^ "Generic Viagra developers queue up, but may have to wait".

Therapeutic indication

"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.

Clinical Uses

"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". "Spreading the Word, but What Word is That? Archived from the original on 28 December 2021. ^ "Approved Viagra copies flood drugstores in Korea". ^ "Viagra prescriptions almost triple in a decade". Archived from the original on 1 July 2024. ^ "MHRA reclassifies Viagra Connect tablets to a Pharmacy medicine". ^ "Viagra to be available without prescription in UK". VIAGRA- sildenafil citrate tablet, film coated Pfizer Laboratories Div Pfizer Inc For most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity. However, VIAGRA may be taken anywhere from 30 minutes to 4 hours before sexual activity. VIAGRA was shown to potentiate the hypotensive effects of nitrates and its administration in patients who use nitric oxide donors such as organic nitrates or organic nitrites in any form is therefore contraindicated [see Contraindications (4.1), Drug Interactions (7.1), and Clinical Pharmacology (12.2)]. When VIAGRA is co-administered with an alpha-blocker, patients should be stable on alpha-blocker therapy prior to initiating VIAGRA treatment and VIAGRA should be initiated at 25 mg [see Warnings and Precautions (5.5), Drug Interactions (7.2), and Clinical Pharmacology (12.2)]. The recommended dose for ritonavir-treated patients is 25 mg prior to sexual activity and the recommended maximum dose is 25 mg within a 48 hour period because concomitant administration increased the blood levels of sildenafil by 11-fold [see Warnings and Precautions (5.6), Drug Interactions (7.4), and Clinical Pharmacology (12.3)]. Consider a starting dose of 25 mg in patients treated with strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, or saquinavir) or erythromycin. Clinical data have shown that co-administration with saquinavir or erythromycin increased plasma levels of sildenafil by about 3 fold [see Drug Interactions (7.4) and Clinical Pharmacology (12.3)]. Consider a starting dose of 25 mg in patients > 65 years, patients with hepatic impairment (e.g., cirrhosis), and patients with severe renal impairment (creatinine clearance <30 mL/minute) because administration of VIAGRA in these patients resulted in higher plasma levels of sildenafil [see Use in Specific Populations (8.5, 8.6, 8.7) and Clinical Pharmacology (12.3)]. VIAGRA is supplied as blue, film-coated, rounded-diamond-shaped tablets containing sildenafil citrate equivalent to 25 mg, 50 mg, or 100 mg of sildenafil.

• 25 mg Viagra may be recommended for men with mild to moderate ED.
• The medication’s effects typically last around 4-6 hours.
• Missing a dose is not typical since Viagra is used as needed.
• To maximize safety, inform your doctor of all health conditions.
• Patients should avoid grapefruit or grapefruit juice when taking Viagra.
• Ensure adequate hydration when using Viagra to prevent dehydration.
• Follow up with your doctor if Viagra doesn't produce expected results.

Tablets are debossed with PFIZER on one side and VGR25, VGR50 or VGR100 on the other to indicate the dosage strengths.

Consistent with its known effects on the nitric oxide/cGMP pathway [see Clinical Pharmacology (12.1, 12.2)], VIAGRA was shown to potentiate the hypotensive effects of nitrates, and its administration to patients who are using nitric oxide donors such as organic nitrates or organic nitrites in any form either regularly and/or intermittently is therefore contraindicated. Although plasma levels of sildenafil at 24 hours post dose are much lower than at peak concentration, it is unknown whether nitrates can be safely co-administered at this time point [see Dosage and Administration (2.3), Drug Interactions (7.1), and Clinical Pharmacology (12.2)].

Mechanism of action

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".

What should I do if I miss a dose of sildenafil?

Archived from the original on 11 October 2007. ^ "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. VIAGRA is contraindicated in patients with a known hypersensitivity to sildenafil, as contained in VIAGRA and REVATIO, or any component of the tablet. Hypersensitivity reactions have been reported, including rash and urticaria [see Adverse Reactions (6.1)].