It is a relatively common medical problem and is estimated to affect million people worldwide, of whom 30 million live in Africa 1. Consumption of sildenafil with illicit drugs was also reported. Angina severe chest pain , unstable or Arrhythmia irregular heartbeat, within the last 6 months or Blood vessel problems eg, aortic stenosis, idiopathic subaortic stenosis or Heart attack within the last 6 months or Heart failure or Hypertension high blood pressure or Hypotension low blood pressure or Retinal disorders eye problem or Retinitis pigmentosa an inherited eye disorder or Stroke within the last 6 months —Should not be used in patients with these conditions. This similarity protects cGMP from degradation because sildenafil can bind to the catalytic site to act as a competitive inhibitor of cGMP-specific PDE-5, the enzyme that normally catalyzes the breakdown of vasodilatory cGMP. Results Socio-Demographic Characteristics A total of 65 men had participated in the study.AdSave Up to 80% on Prescriptions at Over 35, Pharmacies Nationwide with a Free Rx Coupon. Save on 50, Brand Name & Generic Drugs With SingleCare®. Get Your Free Rx Coupon Now!Types: Maintenance, Accute, Branded, Generic. Sildenafil tablets for pulmonary hypertension come in 10mg and 20mg strengths. The usual adult dose is 20mg taken 3 times a day. Doses for children can range from 10mg to 20mg taken 3 times a day, depending on their weight. Do not take it more than 3 times a day. AdBrowse thousands of brands and find deals on sildenafil 25 mg at Amazon®. Shop Now! Discover new arrivals & latest discounts in sildenafil 25 mg from your favorite has been visited by 1M+ users in the past monthTypes: Pharmacy · Pet Supplies · Herbal Supplements.