After two to three hours, the effects start to diminish. How Long It Stays in Your System Viagra has a drug half-life of four hours. This means that the level of sildenafil in your ... but potentially ...

There are no known long-term side effects of tadalafil ... (non-arteritic anterior ischemic optic neuropathy) in a study of sildenafil (Viagra) and optic nerve damage. This condition can develop ...

For most men, sildenafil is a safe and effective treatment for ED when used as prescribed. However, like all drugs, it comes with its own set of potential side effects and interactions.

Vardenafil typically starts working faster, around 15 to 30 minutes after ingestion, while sildenafil ... how long they last, ...