Viagra Tablets 25mg contain the active ingredient, sildenafil and are used for treating erectile dysfunction, also known as male impotence. Insufficient blood flow to the penis during sexual activity prevents the ability to achieve or maintain an erection sufficient for sexual intercourse to take place.
Sildenafil acts on the erectile tissue within the penis, increasing blood flow sufficiently to cause an erection. Viagra tablets are taken within an hour of planned sexual activity and may be effective for up to four hours, provided there is sexual stimulation taking place.
The dose that is required will differ from person to person and lesser dosages than 100mg may be effective.