Table of ContentsView AllTable of ContentsUsesBefore TakingDosageSide EffectsWarnings and Interactions
Table of ContentsView All
View All
Table of Contents
Uses
Before Taking
Dosage
Side Effects
Warnings and Interactions
Erectile dysfunction drugs, known as PDE5 inhibitors, are prescribed for treatingerectile dysfunction (ED). Roughly half of all males between the ages of 40 and 70 have some degree of ED.Around 70% of people who take PDE5 inhibitors can maintain an erection long enough to engage in sexual intercourse.
Despite the widespread popularity of PDE5 inhibitors, there are limitations and risks associated with their use. Though the drugs all work similarly, there are differences that may make some more suitable for you than others.
Jennifer A Smith / Getty Images
In addition to the brand name versions, there are generic versions of sildenafil, tadalafil, vardenafil tablets, and vardenafil dissolvable tablets, The generic versions are generally available at lower prices.
Some PDE5 inhibitors have other approved uses. Sildenafil, for example, is commonly prescribed to treatpulmonary hypertension(high blood pressure in the lungs), in which case it is sold under the brand nameRevatio.Tadalafil is also used for this purpose as Adcirca, as well as for treatingbenign prostatic hyperplasia(BPH, enlarged prostate).
Signs and Symptoms of Erectile Dysfunction
PDE5 inhibitors do not work for everyone. For example, it does not work very effectively for people who have sustained damage to the blood vessels or nerves of the penis as a result of prostate surgery, cardiovascular disease, or diabetes. While PDE5 inhibitors may work at higher doses in these circumstances, other options, such as intraurethral pellet or injectable medication, may be more effective.
As a general rule, your healthcare provider will pinpoint the cause of ED before prescribing any drug. Doing so can better frame expectations.
In addition, a cardiovascular workup should be done since erectile dysfunction can be the first sign of heart issues.
Precautions and Contraindications
Nitrate drugs include:
People who have severe liver or kidney disease also may need to avoid PDE5 inhibitors:
Viagra can be used both in these populations, at the lowest dose of 25 milligrams (mg).
Cialis is the only PDE5 inhibitor that can be taken as needed or in low, daily doses to achieve an erection “on demand.“
As a general rule, the lowest effective dose should always be used. If you are unable to achieve or sustain an erection at the prescribed dose, speak with your healthcare provider to see if an increase in dose is safe and reasonable.
Modifications
The dosages of certain PDE5 inhibitors may need to be adjusted for some people. In general, any PDE5 inhibitor is contraindicated withalpha-blockers(used for urinary issues with BPH) at higher doses.
Adjustments your healthcare provider might make for you include:
Levitra (Vardenafil) vs. Viagra (Sildenafil): Comparing Two ED Drugs
How to Take and Store
For men who dislike or are unable to swallow pills, Staxyn tablets offer an alternative. The pills have a sweet, peppermint flavor and dissolve quickly when placed on the tongue.
PDE5 inhibitors are stored safely at or around 77°F (25°C). Short-term exposure to temperatures of 59° F to 86°F (15° C to 30°C) won’t harm the drug, but never store them in your glove compartment or in direct sunlight. It is best to store the drugs in their original containers or blister-packs until use. Never use expired drugs.
Never take more than the maximum recommended dose or take two different PDE5 inhibitors to “boost” their effects. This will increase the risk and/or severity of side effects.
Treatment Options for Erectile Dysfunction
All PDE5 inhibitors are generally well tolerated. Because they have similar mechanisms of action, they have many of the same side effects. Most of the side effects are mild to manageable, although some require terminating treatment and immediate medical attention.
Common
Common side effects of PDE5 inhibitors include:
The incidence and severity of side effects tend to increase with the dose. If taken in excess, PDE5 inhibitors can cause a rapid drop in blood pressure andsyncope(fainting).
Severe
There are several uncommon side effects that are especially severe and may require emergency intervention.
Among them:
The cause for the hearing loss in users of PDE5 inhibitors is unknown, and Viagra appears to pose the greatest risk.
PDE5 inhibitors are primarily excreted in feces and, to a lesser degree, in urine. Because of their possible impact on the liver and kidneys, hepatic (liver) function and renal (kidney) function may be evaluated prior to the start of treatment, especially if you are at risk of liver disease or kidney disease.
Due to the risk of vision loss, people with a family history of hereditary eye diseases (such ascolor blindness, corneal dystrophy, or retinoblastoma) and those with a prior history of eye stroke should not take PDE5 inhibitors.
Drug-Drug Interactions
Even beyond contraindicated organic nitrates, there is an extensive list of medications and substances that may interact with PDE5 inhibitors.
Even alcohol can cause a transient drop in blood pressure if taken with a PDE5 inhibitor. This is especially true with Cialis (in part because the drug remains in the system for far longer than the other ED drugs).
Alpha-blockers of concern include:
Antihypertensive drug classes of concern include:
CYP450 inhibitors of concern include:
A Word From Verywell
There is no one PDE5 inhibitor that is inherently better than the others. Often, a practitioner will prescribe Viagra to first-time users, in part because of name recognition and cost. But, the simple truth is that others may work just as well, if not better, and offer fewer side effects. You often won’t know until you try several out.
When discussing with your healthcare provider which drug to use, be sure they know about any liver or kidney problems you have, what drugs you are taking (both prescription or over-the-counter), and if you’ve been diagnosed with an eye or cardiovascular disease.
The more a healthcare provider knows about your health, the more likely they will be to find the drug and dose that is just right for you.
How to Cope With Erectile Dysfunction
12 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Gareri P, Castagna A, Francomano D, Cerminara G, De Fazio P.Erectile dysfunction in the elderly: an old widespread issue with novel treatment perspectives.Int J Endocrinol. 2014;2014:878670. doi:10.1155/2014/878670U.S. Food and Drug Administration.Viagra (sildenafil citrate) tablets, for oral use.U.S. Food and Drug Administration.Cialis (tadalafil) tablets, for oral use.U.S. Food and Drug Administration.Levitra (vardenafil hydrochloride), for oral use.U.S. Food and Drug Administration.Staxyn (vardenafil hydrochloride) orally disintegrating tablets.U.S. Food and Drug Administration.Stendra (avanafil) tablets, for oral use.Parsons JK, Dahm P, Köhler TS et al:Management of lower urinary tract symptoms attributed to benign prostatic hyperplasia: AUA guideline.J Urol2020; 204: 799Burnett AL, Nehra A, Breau RH et al:Erectile dysfunction: AUA guideline.J Urol2018; 200: 633Huang SA, Lie JD.Phosphodiesterase-5 (PDE5) inhibitors In the management of erectile dysfunction.P T. 2013;38(7):407-19.Liu B, Zhu L, Zhong J, Zeng G, Deng T.The association between phosphodiesterase type 5 inhibitor use and risk of non-arteritic anterior ischemic optic neuropathy: A systematic review and meta-analysis.Sex Med. 2018;6(3):185-92. doi:10.1016/j.esxm.2018.03.001Barreto MA, Bahmad F.Phosphodiesterase type 5 inhibitors and sudden sensorineural hearing loss.Braz J Otorhinolaryngol.2013;79(6):727-33. doi:10.5935/1808-8694.20130133Tzoumas N, Farrah TE, Dhaun N, Webb DJ.Established and emerging therapeutic uses of PDE type 5 inhibitors in cardiovascular disease.Br J Pharmacol.2019 Nov[Online ahead of print]. doi:10.1111/bph.14920
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Gareri P, Castagna A, Francomano D, Cerminara G, De Fazio P.Erectile dysfunction in the elderly: an old widespread issue with novel treatment perspectives.Int J Endocrinol. 2014;2014:878670. doi:10.1155/2014/878670U.S. Food and Drug Administration.Viagra (sildenafil citrate) tablets, for oral use.U.S. Food and Drug Administration.Cialis (tadalafil) tablets, for oral use.U.S. Food and Drug Administration.Levitra (vardenafil hydrochloride), for oral use.U.S. Food and Drug Administration.Staxyn (vardenafil hydrochloride) orally disintegrating tablets.U.S. Food and Drug Administration.Stendra (avanafil) tablets, for oral use.Parsons JK, Dahm P, Köhler TS et al:Management of lower urinary tract symptoms attributed to benign prostatic hyperplasia: AUA guideline.J Urol2020; 204: 799Burnett AL, Nehra A, Breau RH et al:Erectile dysfunction: AUA guideline.J Urol2018; 200: 633Huang SA, Lie JD.Phosphodiesterase-5 (PDE5) inhibitors In the management of erectile dysfunction.P T. 2013;38(7):407-19.Liu B, Zhu L, Zhong J, Zeng G, Deng T.The association between phosphodiesterase type 5 inhibitor use and risk of non-arteritic anterior ischemic optic neuropathy: A systematic review and meta-analysis.Sex Med. 2018;6(3):185-92. doi:10.1016/j.esxm.2018.03.001Barreto MA, Bahmad F.Phosphodiesterase type 5 inhibitors and sudden sensorineural hearing loss.Braz J Otorhinolaryngol.2013;79(6):727-33. doi:10.5935/1808-8694.20130133Tzoumas N, Farrah TE, Dhaun N, Webb DJ.Established and emerging therapeutic uses of PDE type 5 inhibitors in cardiovascular disease.Br J Pharmacol.2019 Nov[Online ahead of print]. doi:10.1111/bph.14920
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Gareri P, Castagna A, Francomano D, Cerminara G, De Fazio P.Erectile dysfunction in the elderly: an old widespread issue with novel treatment perspectives.Int J Endocrinol. 2014;2014:878670. doi:10.1155/2014/878670U.S. Food and Drug Administration.Viagra (sildenafil citrate) tablets, for oral use.U.S. Food and Drug Administration.Cialis (tadalafil) tablets, for oral use.U.S. Food and Drug Administration.Levitra (vardenafil hydrochloride), for oral use.U.S. Food and Drug Administration.Staxyn (vardenafil hydrochloride) orally disintegrating tablets.U.S. Food and Drug Administration.Stendra (avanafil) tablets, for oral use.Parsons JK, Dahm P, Köhler TS et al:Management of lower urinary tract symptoms attributed to benign prostatic hyperplasia: AUA guideline.J Urol2020; 204: 799Burnett AL, Nehra A, Breau RH et al:Erectile dysfunction: AUA guideline.J Urol2018; 200: 633Huang SA, Lie JD.Phosphodiesterase-5 (PDE5) inhibitors In the management of erectile dysfunction.P T. 2013;38(7):407-19.Liu B, Zhu L, Zhong J, Zeng G, Deng T.The association between phosphodiesterase type 5 inhibitor use and risk of non-arteritic anterior ischemic optic neuropathy: A systematic review and meta-analysis.Sex Med. 2018;6(3):185-92. doi:10.1016/j.esxm.2018.03.001Barreto MA, Bahmad F.Phosphodiesterase type 5 inhibitors and sudden sensorineural hearing loss.Braz J Otorhinolaryngol.2013;79(6):727-33. doi:10.5935/1808-8694.20130133Tzoumas N, Farrah TE, Dhaun N, Webb DJ.Established and emerging therapeutic uses of PDE type 5 inhibitors in cardiovascular disease.Br J Pharmacol.2019 Nov[Online ahead of print]. doi:10.1111/bph.14920
Gareri P, Castagna A, Francomano D, Cerminara G, De Fazio P.Erectile dysfunction in the elderly: an old widespread issue with novel treatment perspectives.Int J Endocrinol. 2014;2014:878670. doi:10.1155/2014/878670
U.S. Food and Drug Administration.Viagra (sildenafil citrate) tablets, for oral use.
U.S. Food and Drug Administration.Cialis (tadalafil) tablets, for oral use.
U.S. Food and Drug Administration.Levitra (vardenafil hydrochloride), for oral use.
U.S. Food and Drug Administration.Staxyn (vardenafil hydrochloride) orally disintegrating tablets.
U.S. Food and Drug Administration.Stendra (avanafil) tablets, for oral use.
Parsons JK, Dahm P, Köhler TS et al:Management of lower urinary tract symptoms attributed to benign prostatic hyperplasia: AUA guideline.J Urol2020; 204: 799
Burnett AL, Nehra A, Breau RH et al:Erectile dysfunction: AUA guideline.J Urol2018; 200: 633
Huang SA, Lie JD.Phosphodiesterase-5 (PDE5) inhibitors In the management of erectile dysfunction.P T. 2013;38(7):407-19.
Liu B, Zhu L, Zhong J, Zeng G, Deng T.The association between phosphodiesterase type 5 inhibitor use and risk of non-arteritic anterior ischemic optic neuropathy: A systematic review and meta-analysis.Sex Med. 2018;6(3):185-92. doi:10.1016/j.esxm.2018.03.001
Barreto MA, Bahmad F.Phosphodiesterase type 5 inhibitors and sudden sensorineural hearing loss.Braz J Otorhinolaryngol.2013;79(6):727-33. doi:10.5935/1808-8694.20130133
Tzoumas N, Farrah TE, Dhaun N, Webb DJ.Established and emerging therapeutic uses of PDE type 5 inhibitors in cardiovascular disease.Br J Pharmacol.2019 Nov[Online ahead of print]. doi:10.1111/bph.14920
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