If you have depression, a healthcare provider may prescribe tricyclic antidepressants. It is not quite clear how the drugs work, but it is thought that they help to keep certain chemicals in the brain longer, which helps to relieve the symptoms of depression. Some tricyclic antidepressants are also approved to treat other conditions, such as bedwetting, anxiety, or obsessive-compulsive disorder (OCD). As with any medication, it is possible to overdose on tricyclic antidepressants. Seek immediate medical attention if you develop any overdose symptoms, such as seizures, hallucinations, or vomiting.