Paruresis

Paruresis ( /ˌpɑrəˈriːsɪs/ PAR-ə-REE-sis) is a type of phobia in which the sufferer is unable to urinate in the (real or imaginary) presence of others, such as in a public restroom. It most commonly affects males, though there are female sufferers too. The analogous condition that affects bowel movement is called parcopresis.