Every manufacturer has a different recommended duration of treatment for his male enhancement pill. Some recommend 3 months course while some even have 6 months to 12 months course duration. Speaking about XTL penis long and strong medicine, it has a recommended course duration of 3 months. When you use a penis enlargement remedy, it is highly recommended to use it for the recommended duration to get the best results. Using the pill over the recommended duration without consulting a doctor or without the manufacturer's approval is not suggested.