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Get generic for Viagra shipped right to your door
Treatment options for erectile dysfunction (ED), like Viagra®, are known to be effective in managing sexual dysfunction. And for most users, the active ingredient in Viagra — sildenafil citrate — is generally considered safe.
Like any medication, however, Viagra can have side effects, ranging from mild symptoms like headaches and stuffy nose to rare but more severe ones, such as vision loss and painful erections. Viagra also can interact with other medications you may be taking.
Below, we explain how Viagra works, common side effects, and drug interactions that you should know about before using this popular erectile dysfunction treatment.
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Viagra (or its generic version, sildenafil) is a generally safe medication that relaxes the blood vessels of your penis to improve blood flow. That said, it can cause some serious medical conditions for some users. Incidences of allergic reactions are possible, but extremely rare.
Approved by the FDA in 1998, sildenafil, the active ingredient in Viagra, belongs to a class of drugs called phosphodiesterase-5 inhibitors, or PDE5 inhibitors. They inhibit the effects of the PDE5 enzyme, which leads to the contraction of the smooth muscles in the blood vessels that supply blood to your penis. This inhibition of PDE5 increases blood flow to the penis, making it easier for you to get and maintain an erection.
Sildenafil is also used for other conditions that can be treated with vasodilation, including pulmonary arterial hypertension (sold as Revatio®).
Overall, Viagra’s safety record is very good. However, like almost every medication, it can cause certain side effects. Most of these are mild and transient, meaning they typically go away as your body processes the medication.
Common side effects of Viagra include:
Headaches
Flushing
Indigestion
Nasal congestion
Back and/or muscle pain
Dizziness
Skin rashes
Vision issues, such as blurred vision, changes in color vision, or other abnormal vision effects
Of these side effects, headaches are generally the most common, affecting between 16 and 28 percent of men who used Viagra in clinical trials.
However, Viagra can also cause more serious side effects, including:
Vision loss
Sudden hearing loss
Priapism (painful and/or long-lasting erections)
These side effects are uncommon. If you develop any serious side effects after using Viagra, it’s important to contact your healthcare provider or seek medical assistance as soon as you can.
Side effects like painful erections certainly sound alarming, but it’s important to put these side effects in context. Only a small percentage of men who use either sildenafil or brand-name Viagra develop any adverse effects, and an even smaller amount have serious issues.
Currently, there is no high-quality evidence to suggest that Viagra causes long-term side effects or health issues. But the serious side effects could cause long-term damage if they are not appropriately addressed.
Priapism (painful and prolonged erections) is one of the most well-known sildenafil side effects. But despite being so well-known, priapism from sildenafil is rare. More common causes of priapism are associated with drugs like antipsychotics and trazodone. Medical issues affecting the pelvis or the blood can also cause priapism.
Put simply, while mild side effects from Viagra do occur, major or dangerous side effects are uncommon. Most men who take the ED medication have a good experience with Viagra and see real improvements in erectile function.
Like many medications, Viagra can interact with other drugs.
Sildenafil, the active ingredient in Viagra, causes a mild drop in blood pressure. In a 2002 study, researchers found that a typical dose of sildenafil decreased systolic blood pressure by 6 mm Hg and diastolic blood pressure by 4.5 mm Hg in a small group of men.
When Viagra is taken with other medications that also reduce blood pressure, it can cause a sudden drop in blood pressure that may be dangerous.
Cardiovascular medications that may interact with Viagra include nitrates such as isosorbide dinitrate (Isordil®) or nitroglycerin (Nitrostat®), as well as alpha-blockers and certain other antihypertensive medications.
Viagra also can interact with medications that inhibit the CYP3A4 enzyme, such as itraconazole, ketoconazole, and the antiretroviral drug ritonavir.
Some recreational drugs, such as “poppers” containing nitrites, can also cause dangerous changes in blood pressure when used with Viagra or other oral drugs for erectile dysfunction.
To avoid any interactions, it’s important to inform your healthcare provider about all medications, supplements, and recreational drugs you currently use before you start taking Viagra. Your healthcare provider will determine if Viagra is safe for you and advise you on how to use it properly.
There’s a common misconception that Viagra and other ED medications have a negative effect on cardiovascular health, or that these medications can trigger myocardial infarction (heart attack) and other medical emergencies. In post-marketing studies, these effects have been seen in temporal relation to Viagra use, but it’s difficult to say how frequent they are or if Viagra is even the cause.
If you’re in good health and don’t suffer from heart health issues, you can likely use these medications safely as directed by your healthcare provider.
That said, if you’ve been diagnosed with a heart condition, it’s best to be cautious when it comes to ED medications and sexual activity.
Before using Viagra or similar medications, make sure to inform your provider about your condition. Let them know if you currently use or have previously used medication for any heart conditions or if you’ve previously suffered a cardiovascular event.
Viagra is generally safe for those with active lifestyles. However, for individuals with serious heart disease or other heart problems, it’s important to seek medical advice before making substantial changes to your activity level.
It’s also important to keep in mind that sex itself is a form of exercise, and enhanced sexual activity is one of the most common Viagra uses. In fact, a 2012 article in the journal Circulation notes that sex is comparable in its level of physical exertion to climbing up several flights of stairs or walking briskly for a short period of time.
As such, if you have a heart condition, the physical activity involved in sex may cause you to experience chest pain or other symptoms.
Make sure to inform your healthcare provider if you experience any concerning problems while having sex or if you feel out of breath or unable to perform during sexual activity.
Viagra is generally safe and effective when it’s used as prescribed. However, taking Viagra on an overly frequent schedule, taking an excessive amount of Viagra, or using Viagra recreationally may increase your risk of experiencing side effects.
Viagra is typically prescribed for use as needed, meaning before sexual activity. Most men who have ED and are prescribed Viagra as an ED treatment are advised to take this medication at least 30 minutes to one hour before they plan to have sex.
You should not take Viagra more than once per day. If you plan to have sex more than once a day and find that Viagra doesn’t last long enough for you, consider talking with your healthcare provider about switching to a different type of ED medication.
Some ED medications, such as tadalafil (the active ingredient in Cialis®), last longer when taken as needed or can be used daily and offer longer-lasting relief from erectile dysfunction.
Another common misconception about Viagra is that it can damage your penis or cause you to become dependent on medication to get an erection.
Contrary to popular belief, Viagra doesn’t have any significant impact on your sex drive or level of sexual stimulation. All it does is make it easier for blood to flow into your penis when you feel sexually aroused.
As we said before, some men who use Viagra may experience priapism — a type of persistent, painful erection that can last for several hours. This is a serious issue that requires urgent medical attention.
But, priapism is extremely rare and affects only a tiny percentage of men who use Viagra or similar medications to treat ED.
As for dependency, there’s no evidence that Viagra is addictive, nor is there any evidence that Viagra can make ED worse.
Most men can take Viagra without any issues. However, as we mentioned above, it’s important not to use Viagra — or at least to talk to your healthcare provider before you consider using this medication — if you:
Have a history of health issues. Viagra may not be safe to use if you have cardiovascular disease or if you’ve previously suffered from a heart attack, stroke, or life-threatening arrhythmia. Likewise, men with sickle cell anemia, retinitis pigmentosa, or Peyronie’s disease should seek medical advice before taking Viagra.
Have blood pressure issues. Given interactions between Viagra and blood pressure, Viagra may not be safe to use if you have hypertension (high blood pressure) or hypotension (low blood pressure). This includes if you currently use medication to control your blood pressure levels.
Have heart failure or unstable angina. These conditions may also make using Viagra or similar ED medications unsafe for you.
Take medication for high blood pressure or angina. Some medicines for managing chest pain, such as nitrates, can cause dangerous interactions when used with Viagra or other PDE5 inhibitors. This includes nitroglycerin, and nitrites like “poppers” can also be dangerous to mix with PDE5 inhibitors.
Have risk factors for non-arteritic anterior ischemic optic neuropathy (NAION). In some cases, Viagra can contribute to an elevated risk of NAION, a rare cause of loss of vision or decreased vision that can occur with PDE5 inhibitors. Make sure to inform your healthcare provider if you have a history of eye problems or if other family members have eye conditions.
Experience hearing loss while using Viagra. If you experience sudden hearing loss, tinnitus, or dizziness while using Viagra, it’s important to stop taking this medication and talk to your healthcare provider as soon as you can.
Used as directed, Viagra can improve your sexual performance and provide relief from erectile dysfunction without significant negative effects on your health. Follow these tips to get the best results from Viagra:
Start with a low or moderate dosage. Viagra comes in several strengths, ranging from 25mg to 100mg per tablet. If you’re concerned about side effects, consider starting with a low or moderate dosage of Viagra.
Take Viagra roughly one hour before sex. As for how to take Viagra for optimal results, you should aim to do so at least 30 minutes to one hour before you plan to have sex. A single dose of Viagra will last for around four hours. You can take Viagra with or without food.
Never take Viagra more than once a day. Viagra is designed for use one time per day, and not more — there is such a thing as too much Viagra. If you prefer a longer-acting medication for ED, consider talking to your healthcare provider about tadalafil (the active ingredient in Cialis).
Avoid drinking alcohol with Viagra. Using Viagra with alcohol can increase your risk of side effects. It’s best to reduce your alcohol consumption or avoid drinking while using Viagra or other ED medications. There are also a select few foods to avoid with Viagra to ensure maximum efficacy.
Avoid over-the-counter Viagra alternatives. Contrary to popular belief, non-prescription products like supplements are not necessarily safer than Viagra. Many contain unlabeled, illicit ingredients, including some that are potentially harmful.
If Viagra doesn’t work, tell your healthcare provider. You may need to try several different dosages of Viagra to identify the one that works best for you. Make sure not to change your recommended dose of Viagra without first talking to your healthcare provider.
Like all prescription drugs, Viagra should be used responsibly. This means following your healthcare provider’s instructions closely and telling them if you notice any issues immediately. In general, though:
Viagra is effective and thoroughly researched. Whether you’re prescribed Viagra or sildenafil, it’s one of the most well-known and effective treatments for erectile dysfunction.
When used as directed, Viagra is a safe medication. It can produce real, noticeable improvements in your sexual function — all without significant negative effects on your health or well-being.
Side effects of Viagra are rare. If you have any negative experience, you should share it with a healthcare professional. You must also inform them of your other health conditions before taking the medication.
Interested in using Viagra? We offer sildenafil, tadalafil, and other FDA-approved medications for ED online, following a consultation with a licensed physician who will determine if a prescription is appropriate.
Learn more about these medications and get a recommendation from a healthcare provider today.
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This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.
Dr. Mike Bohl is a licensed physician, the Director of Medical Content & Authority at Hims & Hers, and a member of the Obesity Medicine Association. Prior to joining Hims & Hers, Dr. Bohl worked in digital health at Ro, focusing on patient education, and as the Director of Scientific & Medical Content at a stealth biotech PBC, working on pharmaceutical drug development. He has also worked in medical journalism for The Dr. Oz Show (receiving recognition for contributions from the National Academy of Television Arts and Sciences when the show won Outstanding Informative Talk Show at the 2016–2017 Daytime Emmy® Awards) and at Sharecare, and he is a Medical Expert Board Member at Eat This, Not That!.
Dr. Bohl obtained his Bachelor of Arts and Doctor of Medicine from Brown University, his Master of Business Administration and Master of Science in Healthcare Leadership from Cornell University, his Master of Public Health from Columbia University, and his Master of Liberal Arts in Extension Studies—Journalism from Harvard University. Dr. Bohl trained in internal medicine with a focus on community health at NYU Langone Health.
Dr. Bohl is Certified in Public Health by the National Board of Public Health Examiners, Medical Writer Certified by the American Medical Writers Association, a certified Editor in the Life Sciences by the Board of Editors in the Life Sciences, a Certified Personal Trainer and Certified Nutrition Coach by the National Academy of Sports Medicine, and a Board Certified Medical Affairs Specialist by the Accreditation Council for Medical Affairs. He has graduate certificates in Digital Storytelling and Marketing Management & Digital Strategy from Harvard Extension School and certificates in Business Law and Corporate Governance from Cornell Law School.
In addition to his written work, Dr. Bohl has experience creating medical segments for radio and producing patient education videos. He has also spent time conducting orthopaedic and biomaterial research at Case Western Reserve University and University Hospitals of Cleveland and practicing clinically as a general practitioner on international medical aid projects with Medical Ministry International.
Dr. Bohl lives in Manhattan and enjoys biking, resistance training, sailing, scuba diving, skiing, tennis, and traveling. You can find Dr. Bohl on LinkedIn for more information.
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