Side Effects

Side effects of avanafil include headache, nausea and dizziness. If these side effects lingers, inform your GP or pharmacist immediately. While trying to switch from a lying to a sitting position, you may experience dizziness or lightheaded; this can be prevented if you get up rather slowly. Always remember that your doctor made this prescription because he/she considers the drug more beneficial to you than chances of side effects. However, many people that use this medication don’t always have severe side effects.

Sexual activity puts extra pressure on your heart, most especially if you have any heart problems. In a situation where you have any heart condition and feel any of these side effects (nausea, dizziness, body pain, fainting etc.) during sexual intercourse, stop immediately and seek medical attention.

In rare cases, sudden blurred vision, which may lead to permanent blindness, in one eye or both, a condition known as NAION, may occur. If this happens, stop your intake of avanafil and get medical attention immediately. Your chances of developing NAION is higher if you have any heart disease, high cholesterol, diabetes, high blood pressure, for those above 50, some eye problems like crowded disk and if you smoke. Other resultant effects include sudden loss of hearing, which may include ringing in the ears and dizziness. Don’t take avanafil any longer and seek medical attention right away if any of these occur.

In case you experience prolonged and painful erection lasting for over 4 hours (which is very rare), stop your drug intake and seek immediate medical attention to avoid permanent occurrence of these side effects. There are rare severe allergic reactions to this drug. Nonetheless, don’t hesitate to get immediate medical attention if you notice these symptoms, severe dizziness, rash, itching/swelling on the face, tongue or throat, and trouble breathing. If you notice other side effects, consult your health practitioner.

Precautions

Before you start taking avanafil, inform your doctor or pharmacist of your allergies as the product may contain inactive ingredients that cause allergic reactions and other problems. Consult your pharmacist for more information.

Also, do well to inform your GP about your medical history before taking this medication. History of heart issues like heart failure, stroke, and chest pain in the previous 6 months.

Other medical conditions like liver and kidney disease, high/low BP, dehydration, penis angulation, fibrosis/scarring, and Peyronie's disease.

The doctor will also check for any previous history of prolonged or painful erection known as priapism and risk factors of priapism like leukaemia, sickle cell anaemia, multiple myeloma, eye conditions including retinitis pigmentosa and sudden decreased vision, bleeding disorders and active stomach ulcers.

This drug can cause dizziness and cause vision changes just like the use of marijuana and alcohol. Avoid driving, use of machinery or anything requiring alertness or clear vision until it is safe. Reduce alcoholic consumption and inform your physician if you use marijuana. Let your doctor know about all the drugs you use. This drug is not commonly used by women. Therefore, it cannot be used during pregnancy or breastfeeding

Interaction with other drugs

Drug interactions may alter the effectiveness of your prescriptions and may heighten your risk for severe side effects. Always tell your doctor or pharmacist of all the products you use and ensure not to start or stop any dosage of your medications without your doctor's permission.

Avanafil can lower blood pressure significantly when combined with nitrates, leading to fainting, dizziness, and in extreme cases heart attack or stroke. Avoid using avanafil with nitroglycerin and isosorbide, which are drugs used to treat chest pain/angina, and recreational drugs called poppers, which contain amyl or butyl nitrite.

Certain Alpha blocker medication like doxazosin and tamsulosin may reduce your blood pressure and cause dizziness or fainting. You may be asked to start with lower dosage of avanafil to reduce low blood pressure risk.

Other drugs can have impact on how long avanafil stays in your body, thereby affecting its workings. Examples are azole antifungals, cobicistat, macrolide antibiotics, HIV protease inhibitors, hepatitis C virus protease inhibitors, nefazodone, etc.

Avoid using the pill with any other medications used in treating ED or pulmonary hypertension like tadalafil and sildenafil.

Overdose

In the event of an overdose and there are severe symptoms like difficulty breathing and passing out, alert 911 immediately or put a call across to any poison control center promptly.