This medication is taken with or without food an hour before sex. Leukemia blood related cancer or Multiple myeloma blood related cancer or Sickle-cell anemia blood disorder —Sildenafil should be used with caution in these patients as problems with prolonged erection of the penis may occur. Ask your doctor if you have any questions. Check with your doctor immediately if any of the following side effects occur: Less common burning feeling in the chest or stomach burning, crawling, itching, numbness, prickling, “pins and needles”, or tingling feelings cloudy or bloody urine. They include dutasteride Avodart, Jalyn and finasteride Propecia, Proscar.Prices for Sildenafil (Viagra) are as low as $ with a GoodRx coupon. See coupons. What are the side effects of Sildenafil (Viagra)? White Oval And Teva – Sildenafil Citrate mg Tablet. This medicine is Blue, Round Tablet Imprinted With “8 8”. Blue Round 8 8 – Sildenafil Citrate mg Tablet.  · For treatment of erectile dysfunction: For oral dosage form (tablets): Adults up to 65 years of age—50 milligrams (mg) as a single dose no more than once a day, 1 hour before sexual intercourse. Alternatively, the medicine may be taken 30 minutes to 4 hours before sexual intercourse. Your doctor may adjust your dose if needed. The typical dose is to take 50 mg of sildenafil (Viagra) by mouth, about 1 hour before sex, as needed. The maximum recommended dose is mg. Don’t take sildenafil (Viagra) more than once daily (at any dose).