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Q:	I am a 15yr old male, 6'0 and 180lbs. I have Hashimoto's and take prednisone 10mg everyday. In the locker room, I see the other guys and I think I may be behind in growth of my privates. I have underarm, private hair and facial hair, but seem to be lacking down below. Can prednisone do this? My doctors also want to switch me from prednisone to cyclosporine. Is this a good idea and will it help my situation?
A:	Being a teenager is a time of change, and questions about body appearance are very normal. Sexual maturity and physical growth occur during adolescence and are collectively known as puberty. Puberty usually begins around ages 10-14 and is complete in about 2-3 years. Each person’s body is the key to when you will begin puberty, and everyone does not start or end at the same time. Growth during puberty is divided into five stages. These stages follow the development of pubic hair, testicular enlargement and penis enlargement for males. Before you go through the changes associated with puberty, you are at Stage 1, and once you become an adult you are in Stage 5. During puberty, the body causes an increase of hormone levels especially the male hormone, testosterone. With the increase of testosterone, you will begin to notice signs of change in your body. The first sign of puberty for males is often enlargement of the testicles, and the development of pubic hair follows not long after testicular growth. Once testicular growth and pubic hair have developed, growth of the penis will become apparent. Although you mentioned a diagnosis of Hashimoto’s treated with prednisone, you did not describe the details of your diagnosis including the time frame of your therapy. Although medications like prednisone can affect growth when taken for long periods of time and at higher doses than yours, 10 mg should not interfere with pubertal development. It is not clear to us whether your concern is the size of your penis or your testicles. Many adolescent boys are concerned about the size of their penis and compare themselves to others. Penis size varies a lot, especially when non-erect. Without an examination, we can’t determine if there is a physical problem. Since you are concerned, we hope you will talk with your doctor at your next visit when you discuss cyclosporine and prednisone. He or she will not be surprised at your question because you will not be the first boy to ask about things like this. If your doctor determines that there is a problem, you may be referred to an endocrinologist or an adolescent medicine specialist. For more information, check out these articles: What Happens When Growing Up as a Boy The Normal Penis Just for Guys – All About Puberty Posted 10-1-04 Do you have a question? As a reminder, this information should not be relied on as medical advice and is not intended to replace the advice of your doctor. Please read our full .