Viagra, Cialis, and More: A List of 9 PDE5 Inhibitors and How They Compare
Key takeaways:
Phosphodiesterase 5 (PDE5) inhibitors are a class of medications that most commonly treat erectile dysfunction (ED). Some PDE5 inhibitors also treat benign prostatic hyperplasia (BPH) and pulmonary arterial hypertension (PAH).
Viagra (sildenafil), Cialis (tadalafil), vardenafil, and Stendra (avanafil) are used to treat ED.
Cialis and its generic can also treat BPH. Certain forms of sildenafil (Revatio, Liqrev) and tadalafil (Adcirca, Alyq, Tadliq) are also approved to treat PAH.
Many PDE5 inhibitors come as both brand-name and lower-cost generic medications. GoodRx can help you save money on your prescription.
Access savings on related medications
Table of contents
Phosphodiesterase 5 (PDE5) inhibitors are a class of medications that work by relaxing blood vessels and smooth muscles in different areas of the body. They’re best known for treating erectile dysfunction (ED), but they can also treat conditions in the lungs and prostate.
You’ve probably heard of Viagra (sildenafil) and Cialis (tadalafil). But there are several other PDE5 inhibitors on the market — each with its own unique characteristics. Here’s how they stack up.
1. Viagra
Viagra and its generic, sildenafil, are FDA approved to treat ED. Viagra was the first PDE5 inhibitor approved for this purpose, and it’s still one of the most popular ED medications today. It comes as a tablet that you take by mouth.
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The typical Viagra dosage ranges from 25 mg up to a maximum of 100 mg, taken 30 minutes to 4 hours before sex. Viagra works best if you take it on an empty stomach. It can kick in as fast as 30 minutes, but it may take up to an hour. Its effects can last for up to 8 hours.
Viagra is available as a brand-name medication and a lower-cost generic. There are many ways to save on Viagra, including using your insurance or GoodRx discounts. At certain pharmacies, you could pay as little as $12.56 for generic Viagra with GoodRx.
2. Revatio
Revatio and its generic, sildenafil, are approved to treat pulmonary arterial hypertension (PAH). PAH causes high blood pressure in the blood vessels that carry blood from the heart to the lungs. Revatio and Viagra both contain sildenafil, but they are not interchangeable.
The typical Revatio dosage for PAH in adults is 20 mg by mouth, three times daily, up to a maximum dosage of 80 mg, three times daily.
Revatio is the only PDE5 inhibitor approved to treat PAH in children; kids as young as 1 year old can get a prescription. The dosage for children is based on their body weight.
You can take Revatio by mouth as an oral tablet or liquid. An intravenous (IV) injection is also available if you cannot take Revatio by mouth for a period of time.
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You may be able to get the best price for Revatio by choosing the lower-cost generic. With GoodRx discounts, you could pay as little as $7.48 at certain pharmacies. But if you’re eligible for a manufacturer savings card, you could pay as little as $0 for brand-name Revatio.
3. Liqrev
Like Revatio, Liqrev contains sildenafil and is approved to treat PAH. But there are a few differences. Liqrev is an oral liquid that’s only approved for use in adults. The Revatio oral liquid, on the other hand, is approved for both adults and children.
The typical Liqrev dosage is the same as Revatio: 20 mg by mouth three times daily, up to a maximum of 80 mg three times daily.
Liqrev is only available as a brand-name product. If you’re eligible, you could pay as little as $0 for Liqrev with a manufacturer copay savings card.
Good to know: Liqrev and Revatio oral liquids contain different inactive ingredients. For example, Liqrev contains strawberry flavoring with acesulfame potassium as the sweetener. Revatio contains grape flavoring with sucralose as the sweetener.
4. Cialis
Cialis and its generic, tadalafil, are approved to treat ED and benign prostatic hyperplasia (BPH). Compared to other PDE5 inhibitors, Cialis lasts longer in the body, so you can take it every day for ED instead of as needed before sex. This can be a more convenient option for some people since it allows for spontaneous sex.
Cialis comes as a tablet that you take by mouth. The typical Cialis dosage for ED depends on whether you’ve been instructed to take it daily or as needed:
Daily: 2.5 mg to 5 mg, once a day
As needed: 5 mg to 20 mg, taken at least 30 minutes before sex
If you’re taking Cialis as needed, it can take about 30 minutes to kick in. But it may take up to 2 hours for it to reach its full effects, which can last up to 36 hours.
For BPH, the usual Cialis dosage is 5 mg once daily. So, if you’re taking Cialis to treat BPH and ED, this is often the dose you’ll take. In this case, Cialis can be a good option for both conditions since other BPH medications can sometimes contribute to sexual problems.
Cialis is available as a brand-name medication and a lower-cost generic. With a free GoodRx discount, you could pay as little as $8.76.
5. Adcirca
Adcirca and its generic, tadalafil, are approved for PAH in adults. It works the same way as Revatio and Liqrev, by relaxing the blood vessels leading from the heart to the lungs. Cialis and Adcirca both contain tadalafil, but they are not interchangeable.
Compared to Revatio, Adcirca is taken less frequently since it lasts longer in the body . The typical Adcirca dosage for PAH is 40 mg (two 20 mg tablets) by mouth once daily.
Adcirca is available as brand-name and generic products. At certain pharmacies, the price of generic Adcirca can be as low as $16.77 with a GoodRx discount. You could also pay as little as $0 for brand-name Adcirca with a manufacturer savings card if you’re eligible.
6. Alyq
Alyq is a branded generic version of Adcirca. In other words, it’s technically a generic medication, but its manufacturer has given it its own brand name. The approved uses and dosage for Alyq are the same as Adcirca.
With GoodRx discounts, the price of Alyq is as low as $18.15 at certain pharmacies.
7. Tadliq
Tadliq is an oral liquid version of tadalafil that’s approved for PAH in adults. It can be a good option if you have difficulty taking pills by mouth. The typical Tadliq dosage is the same as Adcirca and Alyq: 40 mg by mouth once daily.
Tadliq is only available as a brand-name product. You could pay as little as $0 for your prescription with a manufacturer savings card if you're eligible.
8. Vardenafil
Vardenafil is another PDE5 inhibitor that’s approved to treat ED. Only generic versions of vardenafil are on the market today, but it used to be available as name-brand Levitra and Staxyn.
Vardenafil comes as an oral tablet. If you have difficulty swallowing the pills, it’s also available as an orally disintegrating tablet (ODT). The typical vardenafil dosage ranges from 5 mg to 20 mg by mouth 1 hour before sex.
Compared to Viagra and Cialis, vardenafil may work slightly faster. It can start working in as fast as 15 minutes, but it may take up to an hour. Its effects last for up to 5 hours.
Vardenafil is only available as a generic medication. With GoodRx, you could pay as little as $34.00 for the tablets and $11.15 for the ODTs.
9. Stendra
Stendra (avanafil) is the newest PDE5 inhibitor approved by the FDA to treat ED. And like vardenafil, it starts working faster than sildenafil or tadalafil. Avanafil comes as an oral tablet.
The typical Stendra dosage is 50 mg to 200 mg, and it’s taken 15 minutes before sex. Doses that are 100 mg or higher can start to work within 15 minutes. The 50 mg dose can take up to 30 minutes to work.
Unlike the other PDE5 inhibitors for ED, Stendra is only available as a brand-name medication. The best way to save money on Stendra is to use your insurance or a GoodRx discount — whichever has the lowest price. With GoodRx, Stendra’s price is as low as $162.40.
How do you find out which PDE5 inhibitor is right for you?
The right PDE5 inhibitor for you depends on several factors. This can include what you’re treating, your personal preferences, and your insurance coverage.
What condition are you treating? If you’re treating ED, there are several PDE5 inhibitors to choose from. But if you also have BPH, tadalafil (Cialis) can be a good choice.
Can you swallow pills? Some PDE5 inhibitors are only available as oral tablets. Others come as liquids or ODTs to make them easier to take.
Do you have insurance? Some insurance plans may only cover certain PDE5 inhibitors, or they may not cover them at all. In this case, or if you don’t have insurance, you’ll likely get the best price by opting for a PDE5 inhibitor with a lower-cost generic.
Do you have other preferences? Daily tadalafil for ED can be a good option if you don’t want to time your pill around sex. Otherwise, vardenafil and Stendra tend to work the fastest.
Your healthcare provider can help you figure out which PDE5 inhibitor is best for you.
The bottom line
PDE5 inhibitors are medications that treat ED, BPH, and/or PAH. Common examples include sildenafil (Viagra, Revatio, Liqrev), tadalafil (Cialis, Adcirca, Alyq), and vardenafil. The right option for you depends on what you’re treating, your preferences, and your insurance coverage status.
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References
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