Viagra, generic Viagra and Sildenafil all contain the same active ingredient—sildenafil citrate. Sildenafil citrate is a type of medication known as a PDE5 inhibitor. All forms of sildenafil citrate work the same way in the body but differ in their dosage and appearance.
Viagra and generic Viagra are available in 25 mg, 50 mg, and 100 mg tablets.
Sildenafil is available in 20 mg tablets. Multiple tablets of Sildenafil can be combined to equal doses of 40 mg, 60 mg, 80 mg, and 100 mg. When sildenafil citrate is prescribed in these doses for erectile dysfunction, it is considered off-label use of the medication.
This information is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment, and should never be relied upon for specific medical advice. If you have any questions or concerns, please talk to your healthcare provider.