People with heart conditions should never take ED medications without consulting a doctor. Ask your healthcare professional how you should dispose of any medicine you do not use. Key facts It usually takes 30 to 60 minutes for sildenafil to work for erectile dysfunction. However the dose is usually not more than 40 mg 3 times a day. There were highly statistically significant improvements on the two principal IIEF questions frequency of successful penetration during sexual activity and maintenance of erections after penetration on VIAGRA compared to placebo. Figure 6 shows that regardless of the baseline levels of function, subsequent function in patients treated with VIAGRA was better than that seen in patients treated with placebo. Finding an online ED provider can feel overwhelming.Sildenafil is a medication used in the management and treatment of erectile dysfunction and pulmonary arterial hypertension. It is in the phosphodiesterase-5 inhibitor (PDE5-I) class of medications. This activity describes the indications, actions, adverse effects, and contraindications of sildenafil as an agent in the clinical setting. Knowledge . David Muldon. 8 hrs. ago. Show all messages; K. Anderson. K. Anderson; My Profile. AdEnjoy low prices and get fast, free delivery with Prime on millions of products. Browse thousands of brands and find deals on hims ed at Amazon®. Shop Now!Types: Investor Relations · Brain Health Support · Antioxidant · Heart Health Support.