If you’ve ever looked into treatment options for erectile dysfunction (ED), you’ve almost certainly heard of Viagra®.
First launched in the late 1990s, Viagra is arguably the most well-known medication for treating ED.
Viagra contains the active ingredient sildenafil, a PDE5 inhibitor that improves blood flow to your penis and makes it easier to get and maintain an erection.
How safe is Viagra?
For most men, Viagra is a safe and effective medication. However, as with all medications, Viagra can potentially cause side effects and interactions that you should know about before taking it to treat ED.
How Does Viagra Work?
Sildenafil, the active ingredient in Viagra, belongs to a class of drugs called phosphodiesterase type 5 inhibitors, or PDE5 inhibitors.
These medications work by inhibiting the effects of the PDE5 enzyme, which is responsible for contracting the blood vessels that supply blood to your penis.
This increases blood flow, making it easier for you to get an erection. It also can make it easier to maintain an erection during sex, especially if you’re prone to developing erections that aren’t quite firm enough for penetration.
Like many other drugs, sildenafil is also used for other conditions, including pulmonary arterial hypertension (a form of high blood pressure that affects the lungs).
Our guide to how Viagra works goes into more detail about how brand-name Viagra and generic sildenafil work for the treatment of erectile dysfunction.
Is Viagra Safe to Take?
When it’s used as prescribed, Viagra (sildenafil) is generally a safe medication. It was approved by the FDA in 1998, meaning it’s been on the market for more than 20 years. During this time, it has been used by millions of men in the United States and many more worldwide. Overall, Viagra’s safety record is very good. However, like almost every medication, it can cause certain side effects. Most of these side effects are mild and transient, meaning they gradually go away as Viagra is processed by your body.
Common side effects of Viagra include:
Headaches
FlushingDyspepsia (indigestion)
Nasal congestion
Back and/or muscle pain
Dizziness
Skin Rash
Vision issues, such as blurred vision, changes in color vision or other abnormal vision
Of these side effects, headaches are generally the most common, affecting between 16 and 28 percent of men who used Viagra in clinical trials.
Viagra can also cause more serious side effects, including the following:
Ringing in the ears
Shortness of breath
Chest painFainting
Sudden hearing decrease or loss of hearing
Priapism (painful and/or long-lasting erections)
An itching or burning sensation during urination
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 such as fainting or long-lasting, painful erections may sound alarming. However, it’s important to put these side effects in context.
Only a small percentage of men who use either Viagra or generic sildenafil develop any adverse effects, with an even smaller percentage experiencing serious issues. Currently, there is no high quality evidence to suggest that Viagra causes long-term side effects or health issues.
For example, priapism (painful and prolonged erections) is one of the most well-known sildenafil side effects, largely thanks to sensational media reporting.
Despite being so well known, priapism from sildenafil is extremely rare. In fact, just 74 cases of priapism involving sildenafil were recorded in the FDA’s adverse event reporting system during the entire year of 2007, despite millions of men using sildenafil on a regular basis.
Put simply, although mild side effects from Viagra do occur on a somewhat regular basis, major or dangerous effects are very uncommon. Most men who take Viagra have a good experience, with real improvements in erectile function and few issues worthy of concern.
How Often Can You Take Viagra?
Viagra is generally safe and effective when it’s used as prescribed. However, taking Viagra on an overly frequent schedule, or taking an excessive amount of Viagra, may cause your risk of experiencing side effects to increase.
Viagra is typically prescribed for use as needed, meaning before sexual activity. Most men who have ED and are prescribed Viagra as a treatment are advised to take this medication 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 per day and find that Viagra doesn’t last long enough for you, you may want to 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®), can be used daily and offer longer-lasting relief from erectile dysfunction.
Can Viagra Cause Drug Interactions?
Like other medications, Viagra has the potential to interact with other drugs. Some interactions that involve Viagra may be dangerous, particularly those involving other medications that affect your smooth muscle tissue, blood cells, blood flow and/or blood pressure.
Sildenafil, the active ingredient in Viagra, causes a mild drop in blood pressure. In a study from 2002, 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.
By itself, this small drop in blood pressure usually isn’t enough to cause health issues. However, when Viagra is combined with other medications that also reduce blood pressure, it can cause a sudden, significant drop in blood pressure that may be dangerous or life-threatening.
Cardiovascular medications that may interact with Viagra include nitrates (including recreational drugs that contain nitrates), alpha-blockers and other antihypertensive medications.
Viagra can also interact with medications that inhibit the CYP3A4 enzyme, such as itraconazole, ketoconazole and the antiretroviral medication ritonavir.
Some recreational drugs, such as “poppers” containing amyl nitrite, amyl nitrate or butyl nitrate, can also cause dangerous changes in blood pressure when used with Viagra or other drugs for erectile dysfunction.
To avoid interactions, it’s important to inform your healthcare provider about all medications and recreational drugs you currently use or have recently used before using Viagra. Your healthcare provider will determine if Viagra is safe for you, and if appropriate, provide help to make sure you use this medication properly.Our detailed guide to Viagra and nitrates offers more information on these drug interactions and their risks, as well as specific medications to avoid while using Viagra.
Is Viagra Bad for Your Heart?
There’s a common misconception that Viagra and other ED medications have a negative effect on cardiovascular health, or that they can trigger myocardial infarction (heart attack) and other medical emergencies.
There’s currently no scientific evidence that shows that sildenafil, tadalafil, vardenafil (Levitra®) or avanafil (Stendra®) directly cause heart damage.
This means that if you’re in good health and don’t suffer from any cardiovascular health issues, you can use these medications safely as directed by your healthcare provider.
However, if you’ve been diagnosed with a heart condition, it’s best to exercise caution when it comes to ED medications.
Before using Viagra or similar medication, make sure to inform your healthcare 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.
It’s important to keep in mind that sex itself is a mild form of exercise. In fact, a 2012 article in the journal Circulation notes that sex is comparable in physical exertion to climbing up several flights of stairs or walking briskly for a short period of time.
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.
