Sildenafil is a phosphodiesterase inhibitor (PDE-5) used to treat erectile dysfunction (ED). It works by increasing blood flow and oxygen to the penis, helping you more easily attain an erection. Sildenafil is normally taken on an as-needed basis, approximately 30 to 60 minutes prior to sexual activity, although it can be effective in as little as 30 minutes. Its effects typically last for up to 4 to 6 hours; however, this may vary based on individual factors such as age, health status, and concurrent medications. Common side effects of sildenafil may include:

• Flushing

• Dizziness

• Nasal congestion

• Headache

• Indigestion (dyspepsia)

• Visual disturbances (such as a blue tint to vision, blurred vision, or sensitivity to light)

Tadalafil: Commonly sold under the brand name Cialis is a prescription drug that is used to treat erectile dysfunction (ED). It is classified as a phosphodiesterase (PDE) inhibitor, a group of medications that relaxes muscles and increases blood flow to certain areas of the body. Tadalafil can be taken in two ways: 1) as needed prior to sexual activity or 2) once daily at a lower dose for continuous effect. If Tadalafil is taken as needed, it should be taken at least 30 minutes prior to sexual activity, and its effects can last for up to 36 hours. However, when taken daily, it allows for more spontaneous sexual activity without the need to time the dose. Individuals with heart problems, liver or kidney disease, or those taking medications that interact with Cialis should consult with their doctor or health expert before use.

Avanafil is a prescription drug indicated for the treatment of erectile dysfunction. It is designed to work by increasing blood flow and oxygen to the penis, making it easier to get and maintain an erection. While avanafil helps treat ED, it is not intended to increase sexual desire nor cure the condition. Avanafil does not protect against the spread of sexually transmitted infections (STIs) or prevent pregnancy. Avanafil normally starts to work within 15 to 30 minutes of taking a dose, and its effects may last for up to 6 hours. It can be taken with or without food however, it should not be taken more than once within a 24-hour period. Common side effects may Avanafil (Stendra) may include:

• headache

• flushing

• nasal congestion

• back pain

• dizziness

Serious but rare side effects may include vision or hearing changes, chest pain, or a prolonged erection lasting more than 4 hours (priapism), which requires immediate medical attention.

Vardenafil is a prescription drug indicated for the treatment of erectile dysfunction. It widens blood vessels to encourage blood flow to the penis during sexual stimulation. This improved circulation helps patients achieve and maintain an erection sufficient for sexual activity. Vardenafil is normally taken on an as-needed basis, about 30 to 60 minutes prior to sexual activity, and may remain effective for up to 4 to 5 hours. Although Vardenafil is normally well-tolerated, it may cause:

• Vision changes, such as a blue tinge to vision or blurred vision.

• Rare but serious side effects can include sudden hearing or vision loss and priapism (an erection lasting more than 4 hours), which requires immediate medical attention.