Cialis (tadalafil) typically starts working within 30 minutes to an hour after taking it. However, the onset of action can vary depending on individual factors such as metabolism, the presence of food in the stomach, and dosage. In some cases, it may take longer for Generic Cialis to start working, especially if it is taken with a heavy meal. It’s important to note that Cialis requires sexual stimulation to be effective, as it does not cause an erection on its own.