What is the second name for Viagra? Unpacking Sildenafil and Revatio

Sildenafil, the active ingredient in Viagra, was originally synthesized in 1989 by Pfizer chemists looking for a treatment for high blood pressure and angina [1.8.1, 1.8.2]. When answering, 'What is the second name for Viagra?', it's crucial to understand its dual identity as both a generic drug and a medication for different conditions.

Quick Summary

Viagra's second name is its generic name, sildenafil. This active ingredient is also sold under another brand name, Revatio, for treating pulmonary arterial hypertension. Both contain sildenafil but differ in use and dosage.

Key Points

• Sildenafil is the Generic Name: The most direct 'second name' for Viagra is sildenafil, its active medical ingredient [1.2.5].

• Revatio is the Other Brand: Sildenafil is also marketed under the brand name Revatio, but for a different medical condition [1.2.2].

• Different Medical Uses: Viagra is approved for treating erectile dysfunction (ED), while Revatio is used for pulmonary arterial hypertension (PAH) [1.2.1, 1.4.3].

• Mechanism of Action: As a PDE5 inhibitor, sildenafil increases blood flow by preventing the breakdown of a substance called cGMP, which relaxes blood vessels [1.4.1].

• Dosage Varies by Use: Viagra is typically taken as needed in 25-100 mg doses for ED, whereas Revatio is a 20 mg dose taken three times daily for PAH [1.7.2].

• Major Contraindication: Sildenafil must not be used with nitrate medications for chest pain, as this can cause a fatal drop in blood pressure [1.6.2, 1.6.3].

• Generic Equivalence: Generic sildenafil is medically identical to brand-name Viagra and is a more affordable option [1.10.1, 1.10.3].

The Dual Identity of a Famous Blue Pill

When people ask, "What is the second name for Viagra?", the answer has two key parts. The most direct answer is sildenafil, which is the generic name for the active ingredient in Viagra [1.2.5]. However, this same active ingredient, sildenafil, is also sold under another brand name: Revatio [1.2.2]. While they share the same chemical compound, their approved medical uses, dosages, and target patients are distinctly different.

Viagra is specifically approved for the treatment of erectile dysfunction (ED) in men [1.2.1]. It became the first oral treatment for ED approved by the FDA on March 27, 1998, marking a significant moment in pharmaceutical history [1.8.1]. Conversely, Revatio is used to treat pulmonary arterial hypertension (PAH), a serious condition involving high blood pressure in the arteries of the lungs, and is prescribed to both men and women to improve exercise capacity [1.4.3, 1.11.2].

A Serendipitous Discovery

The story of sildenafil is a classic example of drug repositioning. British scientists at Pfizer initially developed the compound, known as UK-92,480, in 1989 to treat hypertension and angina [1.8.1, 1.8.2]. During early clinical trials, the drug showed little effect on angina, but male volunteers reported an unexpected side effect: significant penile erections [1.8.1]. Recognizing the potential, Pfizer pivoted its research and patented sildenafil for the treatment of erectile dysfunction in 1996, leading to the blockbuster drug Viagra [1.8.1, 1.8.2]. Later, its original purpose as a vasodilator was revisited, leading to its approval under the name Revatio for PAH in 2005 [1.4.3].

Mechanism of Action: How Sildenafil Works

Sildenafil belongs to a class of drugs called phosphodiesterase type 5 (PDE5) inhibitors [1.2.5]. Its mechanism depends on the condition being treated:

• For Erectile Dysfunction (Viagra): During sexual stimulation, the body releases nitric oxide (NO) in the penis. NO activates an enzyme that produces cyclic guanosine monophosphate (cGMP), which causes the smooth muscles in the corpus cavernosum to relax, allowing blood to flow in and create an erection [1.4.1]. PDE5 is an enzyme that breaks down cGMP, causing the penis to return to its flaccid state. Sildenafil works by inhibiting PDE5, which allows cGMP to accumulate and remain active longer, thus enhancing and prolonging the erection [1.4.1, 1.4.2]. It's important to note that sexual arousal is required for the medication to work [1.4.4].
• For Pulmonary Arterial Hypertension (Revatio): The same PDE5 enzyme is present in the blood vessels of the lungs [1.3.5]. By inhibiting PDE5, sildenafil allows cGMP to build up, which relaxes and widens the pulmonary arteries. This reduces the blood pressure in the lungs and eases the workload on the heart, improving a person's ability to exercise [1.4.3].

Viagra vs. Revatio: A Detailed Comparison

Understanding the differences between Viagra and Revatio is crucial, as they are not interchangeable despite containing the same active ingredient. You should only be treated with one of these products at a time [1.2.1].

Feature	Viagra	Revatio
Active Ingredient	Sildenafil Citrate [1.10.3]	Sildenafil Citrate [1.2.5]
Primary Use	Erectile Dysfunction (ED) [1.2.1]	Pulmonary Arterial Hypertension (PAH) [1.4.3]
Patient Population	Men with ED [1.2.1]	Men and women with PAH [1.4.3]
Standard Dosages	25 mg, 50 mg, 100 mg, taken as needed before sexual activity [1.7.2]	20 mg taken three times a day [1.7.2]
Administration	Taken approximately 30 minutes to 4 hours before sex, no more than once a day [1.7.2].	Taken at regular intervals, around the same times each day [1.2.1].

Generic Sildenafil: The Affordable Alternative

Since Pfizer's patent expired, generic versions of sildenafil have become widely available [1.8.1]. Generic sildenafil contains the exact same active ingredient as Viagra and is therapeutically equivalent, meaning it is just as safe and effective [1.10.1, 1.10.3]. The main difference is the cost, with generic versions being significantly cheaper [1.10.3]. Generic sildenafil is also available for both ED and PAH indications [1.2.5].

Important Safety Information: Side Effects and Contraindications

Like all medications, sildenafil carries the risk of side effects. Common side effects for both Viagra and Revatio include:

• Headache [1.5.2]
• Flushing (a feeling of warmth) [1.5.2]
• Upset stomach or dyspepsia [1.5.1]
• Nasal congestion [1.5.4]
• Changes in vision, such as a blue tinge or blurred vision [1.5.2]
• Dizziness [1.5.2]

More serious side effects are rare but require immediate medical attention. These include an erection that is painful or lasts longer than 4 hours (priapism), sudden vision loss in one or both eyes, and sudden hearing loss [1.5.2, 1.5.3].

Crucial Contraindications: Sildenafil should never be taken with nitrate medications used for chest pain (like nitroglycerin, isosorbide dinitrate, or isosorbide mononitrate) or with recreational drugs called "poppers" [1.6.2]. The combination can cause a sudden and life-threatening drop in blood pressure [1.6.2, 1.6.3]. It is also contraindicated for use with riociguat (Adempas) [1.6.4]. Patients should inform their doctor of all medications they are taking and their full medical history, especially regarding heart conditions, high or low blood pressure, liver or kidney disease, and certain eye conditions [1.6.2].

Conclusion

So, what is the second name for Viagra? The answer is multifaceted. Sildenafil is its generic name, offering a more affordable but equally effective option for treating erectile dysfunction. At the same time, sildenafil is the engine behind Revatio, a completely different brand targeting a serious lung and heart condition. This dual identity highlights the remarkable journey of a medication that began as a failed heart drug and became a household name for one purpose, while quietly serving a critical role for another.

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Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional before starting or stopping any medication. For more detailed information, you can visit MedlinePlus [1.2.1].

Frequently Asked Questions

Is Revatio the same as Viagra?

No. While both Revatio and Viagra contain the same active ingredient, sildenafil, they are not the same. They are approved for different conditions (Revatio for PAH, Viagra for ED), come in different dosages, and are not interchangeable [1.2.5, 1.7.2].

Is generic sildenafil as effective as Viagra?

Yes, generic sildenafil contains the same active ingredient as Viagra and is considered therapeutically equivalent by the FDA. It works the same way and is equally safe and effective, but is typically much less expensive [1.10.1, 1.10.3].

Can I use Viagra to treat pulmonary hypertension (PAH)?

Viagra is not approved for the treatment of PAH; Revatio is the sildenafil-containing brand specifically dosed and approved for this condition. A doctor should always be consulted for proper treatment [1.4.3, 1.7.2].

Do you need a prescription for sildenafil?

Yes, in the United States, all forms of sildenafil, including Viagra, Revatio, and generic sildenafil, are available by prescription only [1.11.2]. In some countries like the UK, specific formulations may be available over-the-counter from a pharmacist [1.8.1].

What happens if you take sildenafil with nitrates?

Taking sildenafil with nitrate medications (often prescribed for chest pain, like nitroglycerin) can cause a severe and potentially fatal drop in blood pressure. This combination is an absolute contraindication [1.6.2, 1.6.3].

How long does it take for sildenafil to work for ED?

For erectile dysfunction, sildenafil should be taken about 30 minutes to 4 hours before sexual activity. It typically begins to work within 30 to 60 minutes, but sexual stimulation is necessary for it to produce an erection [1.4.4, 1.7.2].

Can women take Viagra or sildenafil?

Sildenafil under the brand name Revatio is approved for use in both men and women for treating pulmonary arterial hypertension (PAH) [1.4.3]. Viagra is not approved for women, but sildenafil is sometimes prescribed 'off-label' for certain types of female sexual dysfunction, though studies have shown inconsistent results [1.10.1, 1.11.4].