The following nonprescription or herbal products may interact with sildenafil: cimetidine Tagamet HB , St. Some medications should not be taken with sildenafil. If you prefer, you may contact the U. Key facts It usually takes 30 to 60 minutes for sildenafil to work for erectile dysfunction. Viagra is not for use by females. If you have erection problems sildenafil works by temporarily increasing blood flow to your penis when you get sexually excited. What alternatives can I use for erectile dysfunction?Viagra Connect contains 50mg sildenafil which relaxes blood vessels to help increase blood flow to the penis. By doing so, this can help a man get and maintain a hard enough erection for sex once he has been sexually aroused. It will not give you an instant erection and can take between 30 minutes to an hour to work. The Savings Offer and Program expire on 12/31/ For further information, call , visit test1.ru, or write: Viatris Inc., P.O. Box , Mission, KS Eligible patients may save on their VIAGRA® (sildenafil citrate) prescription with the VIAGRA savings card. About sildenafil (Viagra) Sildenafil is a medicine used to treat erection problems (erectile dysfunction). Sildenafil is also sometimes used to treat pulmonary hypertension (high blood pressure in the blood vessels that supply the lungs). If you have erection problems sildenafil works by temporarily increasing blood flow to your penis when.