It is important to tell your doctor about any heart problems you have now or may have had in the past. Please expect up to 4 to 6 weeks for reimbursement. Stop taking VIAGRA and call your healthcare provider right away if you have any sudden vision loss sudden hearing decrease or hearing loss. If you already use medicine for high blood pressure hypertension , sildenafil could make your blood pressure go too low. Storage Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.Key facts. Sildenafil (Viagra) is a medicine used to treat erectile dysfunction (ED, also called impotence). Sildenafil works by helping to relax the blood vessels in the penis, allowing more blood to flow in and cause an erection. You should take sildenafil about an hour before planned sexual activity, so it has time to work. Rx: Priska 20mg Tablet. ₱ Sildenafil mg Film – Coated Tablet Selective Phosphodiesterase-5 (PDE-5) Inhibitor 1 pc Tablet REMINDER: A doctor’s prescription . Shop for Rx – Erectile Dysfunction Online at Southstar Drug Free Shipping for Orders Over ₱1, Now Serving Orders Nationwide Order Now!