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Sildenafil is an erectile dysfunction (ED) drug. It is the active ingredient in the brand-name drug Viagra. The generic version of Viagra also uses the name sildenafil.

This article takes a closer look at sildenafil, ED, and how the drug works to relieve the condition.

Sildenafil is a popular treatment for ED. The main ingredient in sildenafil is sildenafil citrate. Inactive ingredients include:

  • microcrystalline cellulose
  • anhydrous dibasic calcium phosphate
  • croscarmellose sodium
  • magnesium stearate
  • hypromellose
  • titanium dioxide
  • lactose
  • triacetin
  • artificial colors

Viagra is just one brand-name option containing sildenafil. Other products might use different inactive ingredients.

Another brand-name option containing sildenafil is Revatio. In addition to treating ED, Revatio also treats pulmonary hypertension (PH). PH involves high blood pressure in the right side of the heart and the arteries of the lungs.

A person who wishes to use sildenafil for ED should contact a doctor, as the medication is available by prescription only in the United States.

People with ED have difficulty getting or maintaining an erection. It is a widespread condition, but many people find it difficult to discuss.

Some risk factors for ED include:

  • being older
  • having certain conditions or medical issues
  • having mental health issues
  • having excess weight
  • smoking
  • taking certain medications

ED may sometimes be a sign of an underlying condition. This is why people should contact a doctor if they experience difficulty getting or maintaining an erection.

Some conditions that may have ED as a sign include:

When a pharmaceutical company develops a new drug, they may have exclusivity for a specific amount of time. This can sometimes be up to 20 years. Once this period of exclusivity elapses, competitors are free to market generic versions of a drug.

Generic versions must contain the same active ingredients as the brand-name drug. The active ingredient is the element of a medication that makes it effective against whatever it is treating.

The Food and Drug Administration (FDA) allows differences in inactive ingredients, but the drug companies must prove that they do not interfere with the effectiveness or function of the drug.

Viagra is the brand-name version of sildenafil. Since its exclusivity period expired in April 2020, generic versions of sildenafil are available from alternative drug companies that typically offer more affordable pricing.

One observable difference between Viagra (brand-name) and sildenafil (generic) is the pill’s appearance. While Viagra pills are blue, sildenafil pills are white. Both medications are safe and effective.

Sildenafil falls into a class of medications called phosphodiesterase type 5 (PDE5) inhibitors. They inhibit phosphodiesterase enzymes, which degrade the molecules that relax the muscle tissue. This allows for increased blood flow, causing an erection.

Sildenafil does not cure ED. However, it can help treat the symptoms of the condition.

The pills come in strengths of 25 milligrams (mg), 50 mg, and 100 mg. People generally take 50-mg pills approximately 1 hour before sex. No matter the dosage, a person should not take sildenafil more than once per day.

The drug is fast-acting, and its effects typically last about 1 hour. It is important to note that sildenafil does not instantaneously produce an erection. A person must be sexually aroused for the drug to work. Sildenafil also does not affect sex drive.

Regarding the safety of sildenafil, one 4-year long study found that long-term use of the drug is generally safe. People are more likely to experience adverse reactions to the drug if they take more than the recommended amount.

Side effects

Some common side effects of sildenafil include:

  • headaches
  • flushing
  • gastrointestinal distress
  • nausea
  • muscle aches and pains
  • dizziness
  • rashes

Other warnings

It is possible to take too much sildenafil. If a person overdoses on this medication, they should contact Poison Control on 800-222-1222 or go to the emergency room.

It is important to note that sildenafil is not a contraceptive, so it does not prevent pregnancy. Also, it does not protect against sexually transmitted infections.

Adjustments to sildenafil dosing may be necessary for adults over the age of 65 years.

Below is a list of some of the best ED treatments for a person to consider.

Please note that the writer of this article has not tried any of these products. All information presented here is purely research-based.

  • Roman offers online support for ED and other health conditions. It has a team of qualified healthcare professionals who review a person’s medical information. The company also has a licensed pharmacy and offers both generic and brand-name drugs. Learn more about Roman here.
  • BlueChew offers chewable sildenafil tablets, which some people may prefer. The company has a medical team that helps ensure that people get the proper treatment. Learn more about BlueChew.
  • Hims offers sildenafil pills and other ED options for a person to explore. The company puts people in contact with licensed medical professionals who ensure that they get treatment tailored to their needs. Learn more about Hims here.

If a person cannot take sildenafil, wishes to avoid it, or wants to try something else, there are other options to treat ED.

Other PDE5 inhibitors include:

  • avanafil (Stendra)
  • tadalafil (Cialis)
  • vardenafil (Levitra)

Other treatment options include:

  • erectile dysfunction pumps
  • penile implants
  • penile injections
  • prescription testosterone

People may also wish to consider making lifestyle adjustments to help manage the symptoms of ED. These may include:

Mental ill-health may also contribute to ED. Anxiety and stress about sex, for example, can make it more difficult for a person to get or maintain an erection. Talking with a mental health professional may help.

A person should contact a doctor for a sildenafil prescription, as the drug is not available over the counter.

It is vital for a person to talk with a doctor if they take other medications, as these may interact with sildenafil. Medications that may negatively interact with sildenafil include those for blood pressure.

Someone who is using sildenafil and experiences any of the following side effects should contact a doctor right away:

Some other potential adverse reactions associated with sildenafil include low blood pressure and hearing loss.

Sildenafil is the generic version of the brand-name drug Viagra. Sildenafil is an effective ED drug that is available at a fraction of the cost of Viagra.

Despite its status as a generic drug, it is just as safe and effective as Viagra. However, like Viagra, there are potential side effects and drug interactions associated with its use.

People who experience ED should talk with a doctor to discuss their treatment options.