The Doctors welcome urologist Dr. Aaron Spitz to discuss a sensitive topic for some men -- the size of their manhood, or the perception that they are too small.

Watch: How to Treat an Injured Manhood

They discuss penile dysmorphic disorder, a psychological disorder in which an individual is excessively concerned about and preoccupied with a perceived deficit in size. Dr. Spitz notes that often, the men who are worried they are too small, have partners who are actually very satisfied. 

He says most men fall into the average size (which is 5.5 inches) and people's perceptions about size are skewed due to pornography. 

Watch: Curved "Manhood" Increases Cancer Risk    

Dr. Spitz says it is important that people with penile dysmorphic disorder first need to be educated that the size of one's manhood is often drastically different in a non-aroused state compared to when aroused. He also notes when someone looks at their own penis and then compares it to another person, their perception will not be a true and accurate representation of what they have. He says if a man really needs to get a true look at their penis to use a full-length mirror to size yourself up.

As for altering the size of the penis, Dr. Spitz urges men to not attempt this, because the pills, ointments, devices, and surgeries are most often not effective and waste of time and money.