Achluophobia is the fear of darkness. The document defines achluophobia and discusses its symptoms and causes, which include feelings of being scared, tired, or confused in the dark due to thoughts of something unreal. The document also outlines treatments for achluophobia, such as behavior therapy, psychotherapy, relaxation techniques, and medication. In conclusion, the document defines achluophobia, discusses its symptoms and causes, and describes common treatments which involve behavior therapy, psychotherapy, relaxation, and medication.