Sildenafil

💊 What is Sildenafil used for?

• •Erectile dysfunction (ED)

How it works

The label describes sildenafil as a selective inhibitor of an enzyme called phosphodiesterase type 5 (PDE5). The label text provided does not explain this further.

How it is usually taken

• •The label says it is usually taken as needed, before sexual activity, within a time window set by the label. It may be taken with or without food. The label sets a maximum of once per day. Follow the instructions from your prescriber or pharmacist.

Comes as

• •Film-coated tablets, 25 mg (white, round)
• •Film-coated tablets, 50 mg (white, round)
• •Film-coated tablets, 100 mg (white, round)

⚠️ Sildenafil side effects

🛑 Who should not take Sildenafil, and who should be careful

The label says not to take it if

• 🚨You take nitrates or other nitric oxide donors (such as organic nitrates or nitrites in any form), which are used to treat chest pain (angina). The label says this combination is contraindicated.
• 🚨You take a guanylate cyclase stimulator such as riociguat (Adempas). The label says this combination is contraindicated.
• 🚨You have a known allergy (hypersensitivity) to sildenafil or any ingredient in the tablet. The label says reactions have included rash and hives (urticaria).
• 🚨You take other PDE5 inhibitors, including Revatio or other sildenafil products for pulmonary arterial hypertension. The label says the safety of combining them has not been studied.

Tell your doctor before taking it if

• •Tell your healthcare provider about your heart health. The label says sexual activity can put extra strain on the heart, and sildenafil is not recommended for men for whom sexual activity is inadvisable because of their cardiovascular status.
• •Tell your provider if you have had a heart attack, stroke, or life-threatening irregular heartbeat in the last 6 months. The label says there are no controlled clinical data on safety or efficacy in this group, so use requires caution.
• •Tell your provider if you have low resting blood pressure, high blood pressure, heart failure, or coronary artery disease with unstable angina. The label says use in these groups should be done with caution.
• •Tell your provider if you have a history of NAION or a 'crowded' optic disc. The label says use requires caution in these cases.
• •Tell your provider if you have a condition that may raise the risk of priapism, such as sickle cell anemia, multiple myeloma, or leukemia, or a deformity of the penis such as Peyronie's disease. The label says use should be cautious in these cases.
• •Tell your provider if you take an alpha-blocker. The label says you should be stable on alpha-blocker therapy before starting sildenafil.
• •Tell your provider if you have left ventricular outflow obstruction (such as aortic stenosis) or severely impaired autonomic control of blood pressure. The label says to use caution.
• •The label says sildenafil does not protect you or your partner from sexually transmitted diseases, including HIV.
• •The label says that if you need emergency care for a heart problem, your provider will need to know when you last took sildenafil. Tell all your healthcare providers that you take it.

🔀 Sildenafil with other medicines, food and alcohol

The label says to discuss these with your doctor or pharmacist

• •Nitrates and other nitric oxide donors: contraindicated. The label says sildenafil can strongly increase their blood pressure-lowering effect.
• •Alpha-blockers and other blood pressure medicines: can add to blood pressure lowering and may cause symptomatic low blood pressure. The label says the starting dose may need to be lower.
• •Amlodipine: the label says it can add to blood pressure lowering when taken with sildenafil.
• •Ritonavir: the label says it greatly increases sildenafil levels, so the label sets a lower maximum dose.
• •Other CYP3A4 inhibitors such as ketoconazole, itraconazole, saquinavir, and erythromycin: the label says these can increase sildenafil levels, and a lower starting dose may be considered.
• •Riociguat (a guanylate cyclase stimulator): contraindicated.

Alcohol and food

The label says sildenafil may be taken with or without food. The label text provided does not address alcohol.

🤰 Sildenafil in pregnancy and breastfeeding

Pregnancy

The label says sildenafil is not indicated for use in females. It also says there are no data on use in pregnant women. In animal studies, no adverse developmental outcomes were seen at the doses described in the label.

Breastfeeding

The label does not say.

🗓️ Storage, missed doses and taking too much

Storage

The label says to store at 20 to 25 degrees C (68 to 77 degrees F), which is controlled room temperature.

If a dose is missed

The label does not say.

If too much is taken

The label says that in studies of healthy volunteers, single doses above the recommended range caused similar side effects, which were more frequent and more severe. In cases of overdose, standard supportive measures are used as needed. The label says renal dialysis is not expected to speed up removal of sildenafil, because it is highly bound to plasma proteins and is not eliminated in urine.

🗒️ Questions to ask about Sildenafil

• Is my heart healthy enough for sexual activity while I take this medicine?
• Do I take any nitrates or other medicines that could be dangerous with sildenafil?
• What should I do if an erection lasts longer than 4 hours?
• What should I do if I notice sudden vision or hearing changes?
• Are any of my other medicines, such as blood pressure medicines or HIV medicines, known to interact with sildenafil?
• How much should I take, and how often, based on my own health?
• Does this medicine protect against sexually transmitted diseases?

❓ Sildenafil: frequently asked questions