Vilitra is a medication that contains vardenafil as its active ingredient, and it's primarily used to treat erectile dysfunction (ED) in men. The duration of action of Vilitra can vary depending on the individual and several other factors. However, generally speaking:

Onset of Action: Vilitra typically starts working within 30 to 60 minutes after ingestion. This means that it may take around half an hour to an hour for Vilitra to begin showing its effects in terms of improving erectile function.

Duration of Action: The effects of Vilitra can last for about 4 to 6 hours. During this time, a man who has taken Vilitra may find it easier to achieve and maintain an erection when sexually stimulated.

It's essential to note that the duration of action can be influenced by factors such as the individual's metabolism, the dosage of Vilitra taken, the presence of other medical conditions, and whether the medication is taken on an empty stomach or with food. It's always best to follow the prescribed dosage and recommendations provided by a healthcare professional when using Vilitra or any other medication for erectile dysfunction.