For small penises caused by low testosterone levels, testosterone supplementation between the ages of 6 months and 1 year can help improve the condition. In adulthood, no medication can increase the size of the penis, regardless of the cause. The most common cause of micropenis is low testosterone levels, which can lead to a short, small penis in men. In this case, after the application of testosterone undecanoate and other drugs for treatment, can play a certain role in improving. For penile shortness caused by congenital deformity and dysplasia, testosterone supplementation cannot increase the size of the penis. In this case, surgery such as implantation of prosthesis can be considered after adulthood. For men, there is no effective way to enlarge the penis. If you have a small penis, you should consult a doctor to confirm the diagnosis, combine the results of the examination, and follow the doctor’s instructions for treatment.