See the DrugPatentWatch profile for Viagra
Viagra, known chemically as sildenafil, was launched by Pfizer in the United States on April 6, 1998 [1]. It is prescribed for erectile dysfunction [2].
When did Viagra get FDA approval?
The U.S. Food and Drug Administration (FDA) approved Viagra on March 27, 1998, making it the first oral medication for erectile dysfunction [1].
How long has Viagra been on the market?
As of 2024, Viagra has been available on the market for over 25 years [1].
What is the patent status of Viagra?
Pfizer held the original patent for Viagra, which provided market exclusivity. However, patents expire, opening the door for generic competition. Information on the current patent and exclusivity status for Viagra can be found at DrugPatentWatch.com [3].
When does Viagra's patent expire?
The primary patents for Viagra have expired in many major markets, including the United States and Europe [3]. The initial U.S. patent was set to expire in 2015, but various legal challenges and extensions could affect exact dates [3].
Are there generic versions of Viagra available?
Yes, generic versions of sildenafil are available. Following the expiration of Pfizer's key patents, other pharmaceutical companies have been able to produce and market generic versions of the drug [3].
How much does Viagra cost?
The cost of Viagra can vary significantly depending on the dosage, the number of pills, and whether a brand-name or generic version is purchased. Generic sildenafil is generally less expensive than brand-name Viagra. Prices can also differ between pharmacies and insurance coverage [4].
What are the risks and side effects of Viagra?
Common side effects of Viagra include headache, flushing, indigestion, nasal congestion, and visual disturbances [2]. More serious, though rare, side effects can include prolonged erections (priapism), sudden vision loss, or sudden hearing decrease [2]. Viagra should not be taken by individuals using nitrate medications due to a risk of severe hypotension [2].
Who manufactures Viagra?
Viagra was developed and is manufactured by Pfizer [1]. However, generic sildenafil is produced by multiple pharmaceutical companies globally [3].
How does Viagra work?
Viagra works by increasing blood flow to the penis during sexual stimulation. It inhibits an enzyme called phosphodiesterase type 5 (PDE5), which helps the smooth muscles in the penis relax and allows for an erection [2].
What is the difference between Viagra and Cialis?
Viagra (sildenafil) and Cialis (tadalafil) are both oral medications used to treat erectile dysfunction, but they differ in their active ingredients, duration of action, and onset of effect. Viagra typically lasts for about 4-5 hours, while Cialis can last up to 36 hours. Cialis also has a faster onset of action for some individuals. Both drugs are PDE5 inhibitors but work slightly differently [5].
How effective is Viagra for erectile dysfunction?
Clinical trials have shown Viagra to be effective in helping men achieve an erection sufficient for sexual intercourse. Its effectiveness can depend on the cause of erectile dysfunction and individual response [2].
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1. "Sildenafil." Wikipedia, Wikimedia Foundation, 11 Nov. 2023, en.wikipedia.org/wiki/Sildenafil.
2. "Viagra." RxList, 2023, www.rxlist.com/consumerviagracialis/drugs-conditions.htm.
3. DrugPatentWatch.com.
4. "Viagra Prices, Coupons & Patient Assistance Programs." Drugs.com, 2023, www.drugs.com/price-guide/viagra.
5. "Viagra vs. Cialis: What's the Difference?" Healthline, 7 Apr. 2023, www.healthline.com/health/erectile-dysfunction/viagra-vs-cialis.