Children—Use is not recommended. Contact your medical provider if you experience any side effects during treatment. Ask your pharmacist for a list of the ingredients. Alternatively, the medicine may be taken 30 minutes to 4 hours before sexual intercourse. Sildenafil treats PAH by relaxing the blood vessels in the lungs to allow blood to flow easily. You are encouraged to report adverse events related to Viatris products by calling U. Payment options: Consider how you’d like to pay.The Savings Offer and Program expire on 12/31/ For further information, call , visit , or write: Viatris Inc., P.O. Box , Mission, KS Eligible patients may save on their VIAGRA® (sildenafil citrate) prescription with the VIAGRA savings card. 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.  · Viagra comes as an oral tablet that contains the active drug sildenafil. Sildenafil is also available in generic form. Viagra is classified as a phosphodiesterase type 5 (PDE5) inhibitor.