Indication
Sildenafil is a phosphodiesterase-5 (PDE5) inhibitor indicated for the treatment of erectile dysfunction (ED).

Do not take Sildenafil if you:

• take any medicines called nitrates, often prescribed for chest pain, or guanylate cyclase stimulators like Adempas (riociguat) for pulmonary hypertension. Your blood pressure could drop to an unsafe level.

• are allergic to Sildenafil, as contained in Sildenafil and REVATIO, or any of the ingredients in Sildenafil.

Warnings & Precautions
Discuss your health with your doctor to ensure that you are healthy enough for sex. If you experience chest pain, dizziness, or nausea during sex, seek immediate medical help.

Sildenafil can cause serious side effects. Rarely reported side effects include:

• An erection that will not go away (priapism). If you have an erection that lasts more than 4 hours, get medical help right away. If it is not treated right away, priapism can permanently damage your penis.

• Sudden vision loss in one or both eyes. Sudden vision loss in one or both eyes can be a sign of a serious eye problem called non-arteritic anterior ischemic optic neuropathy (NAION). Stop taking Sildenafil and call your healthcare provider right away if you have any sudden vision loss.

• Sudden hearing decrease or hearing loss. Some people may also have ringing in their ears (tinnitus) or dizziness. If you have these symptoms, stop taking Sildenafil and contact a doctor right away.

Before Taking Sildenafil
Before you take Sildenafil, tell your healthcare provider if you:

• have or have had heart problems such as a heart attack, irregular heartbeat, angina, chest pain, narrowing of the aortic valve, or heart failure.

• have had heart surgery within the last 6 months.

• have pulmonary hypertension.

• have had a stroke.

• have low blood pressure, or high blood pressure that is not controlled.

• have a deformed penis shape.

• have had an erection that lasted for more than 4 hours.

• have problems with your blood cells such as sickle cell anemia, multiple myeloma, or leukemia.

• have retinitis pigmentosa, a rare genetic (runs in families) eye disease.

• have ever had severe vision loss, including an eye problem called NAION.

• have bleeding problems.

• have or have had stomach ulcers.

• have liver problems.

• have kidney problems or are having kidney dialysis.

• have any other medical conditions.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Drug Interactions
Sildenafil may affect the way other medicines work, and other medicines may affect the way Sildenafil works, causing side effects. Especially tell your healthcare provider if you take any of the following:

• medicines called nitrates.

• medicines called guanylate cyclase stimulators such as Adempas (riociguat).

• medicines called alpha-blockers such as Hytrin (terazosin HCl), Flomax (tamsulosin HCl), Cardura (doxazosinmesylate), Minipress (prazosin HCl), Uroxatral (alfuzosin HCl), Jalyn (dutasteride and tamsulosin HCl), or Rapaflo (silodosin). Alpha-blockers are sometimes prescribed for prostate problems or high blood pressure. In some patients, the use of Sildenafil with alpha-blockers can lead to a drop in blood pressure or to fainting.

• medicines called HIV protease inhibitors, such as ritonavir (Norvir), indinavir sulfate (Crixivan), saquinavir (Fortovase or Invirase), or atazanavir sulfate (Reyataz).

• some types of oral antifungal medicines, such as ketoconazole (Nizoral) and itraconazole (Sporanox).

• some types of antibiotics, such as clarithromycin (Biaxin), telithromycin (Ketek), or erythromycin.

• other medicines that treat high blood pressure.

• other medicines or treatment options for ED.

Sildenafil contains Sildenafil, which is the same medicine found in another drug called REVATIO. REVATIO is used to treat a rare disease called pulmonary arterial hypertension (PAH). Sildenafil should not be used with REVATIO or with other PAH treatments containing Sildenafil or any other PDE5 inhibitors (such as Adcirca [tadalafil]).

Important Usage Information
Sildenafil does not protect against sexually transmitted diseases, including HIV.

Most Common Side Effects
The most common side effects of Sildenafil include: headache; flushing; upset stomach; abnormal vision, such as changes in color vision (such as having a blue color tinge) and blurred vision; stuffy or runny nose; back pain; muscle pain; nausea; dizziness; rash.

How to Take Sildenafil
Sildenafil can be taken with or without food. Take about 30 minutes to 1 hour before anticipated sexual activity.
Do not take Sildenafil more than once in a 24-hour period or within 24 hours of any other ED medications or PDE-5 inhibitors.
You should take the medication exactly as prescribed. If your symptoms are not improving or you have any questions about changing or stopping medication, reach out to your healthcare provider for guidance.

Medical History and Risks
It is important to share your full medical history with your provider. In particular, tell your provider if you have or have had:

• cardiovascular risk that prevents you from partaking in sexual activity.

• chest pain requiring nitroglycerin.

• predisposition to priapism (painful erection that lasts >4 hours).

• ventricular outflow obstruction (e.g., aortic stenosis, idiopathic hypertrophic subaortic stenosis).

• severely impaired autonomic control of blood pressure.

• myocardial infarction, stroke, or life-threatening arrhythmia.

• low or high blood pressure.

• cardiac failure or coronary artery disease causing unstable angina.

• anterior ischemic optic neuropathy (NAION) or a “crowded” optic disc.

• bleeding disorders or ulcers.

• kidney or liver disease.

• pulmonary hypertension.

• retinitis pigmentosa.

Withholding or providing inaccurate information about your health and medical history in order to obtain treatment may result in harm, including, in some cases, death.

Serious Side Effects
If you are experiencing a medical emergency, call 911 or seek immediate medical attention.

You or a caregiver should carefully monitor for these side effects, especially in the beginning of treatment:

• Cardiac risk of sexual activity: ED medication should not be used by men for whom sexual activity is not advised because of their underlying cardiovascular status.

• Prolonged erections: Seek immediate emergency treatment for an erection lasting more than 4 hours.

• Effects on the eye: Seek medical care and stop medication if you experience a sudden loss of vision in one or both eyes. Sudden loss of vision could be a sign of non-arteritic anterior ischemic optic neuropathy (NAION).

• Sudden hearing loss: Stop medication and seek prompt medical attention if you experience a sudden decrease or loss of hearing, which may be accompanied by ringing in the ears.

• Co-administering with alpha-blockers or other blood pressure-lowering drugs: If you are taking a medication to lower your blood pressure or taking an alpha-blocker, Sildenafil may increase the blood-pressure-lowering effect, leading to a sudden drop in blood pressure. When starting Sildenafil, monitor carefully for signs of low blood pressure, including dizziness, lightheadedness, or fainting.

• Co-administering with ritonavir: If you are taking ritonavir at the same time as Sildenafil, ritonavir can increase the amount of Sildenafil in your system. Monitor for lowered blood pressure, fainting, and prolonged erection.

• Combination with other PDE-5 inhibitors: Do not take Sildenafil more than once in a 24-hour period or within 24 hours of any other ED medications or PDE-5 inhibitors.

• Effects on bleeding: Sildenafil has no effect on bleeding time when taken alone or with aspirin; however, there have been reports of bleeding with the use of Sildenafil. Tell your provider if you have a history of bleeding disorders or ulcers.

• Sexually transmitted infections: Sildenafil does not protect against sexually transmitted diseases. Use safe sex practices.

Reporting Adverse Events
You are encouraged to report negative side effects of prescription products to the FDA. Visit:
https://www.fda.gov/safety/medwatch-fda-safety-information-and-adverse-event-reporting-program
or call 1-800-FDA-1088.