Viagra is available in 3 different dosages:
50mg dose – the standard dose. Most men start on this one. It’s highly effective but keeps the risk of side effects to a minimum.
100mg dose – high strength. The 100mg dose is for those men who do not see results from the smaller dose.
25mg dose – the low-strength dose. 25mg doses are intended for men who experience side effects regularly at larger doses.
Unbranded Sildenafil is available in the same strengths.