Push the plunger of the syringe, then insert the tip into the bottle while holding the bottle upright on a flat surface. These results demonstrated that the effect of VIAGRA on the primary endpoint was statistically non-inferior to placebo. Sexual activity may be a strain on your heart, especially if you have heart disease. Storage Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Sildenafil treats erectile dysfunction by increasing blood flow to the penis during sexual stimulation. Vardenafil usually works for 4 to 5 hours. This medicine works best when you take it on an empty stomach an hour before sex.Sildenafil (Viagra) is only approved by the FDA to treat erectile dysfunction in males. While some studies did look at the use of sildenafil (Viagra) in females, more research is . Sildenafil citrate is a white to off-white crystalline powder with a solubility of mg/mL in water and a molecular weight of VIAGRA is formulated as blue, film-coated rounded-diamond-shaped tablets equivalent to 25 mg, 50 mg and mg of sildenafil for oral administration. BlueChew vs. Hims: Chewable Viagra to Try in Medically reviewed by Alexandra Perez, PharmD, MBA, BCGP BlueChew and Hims both offer chewable versions of ED medications such as sildenafil.