An association has been observed between obsessive symptoms in Obsessive Compulsive Disorder (OCD) and psychotic symptoms in schizophrenia, being sometimes difficult to establish a clear limit between them. The term “schizo-obsessive disorder” was proposed to describe the resulting disorder of comorbidity of OCD and schizophrenia, although it has not been definitely settled.

To analyze the incidence of coexistence of OCD and schizophrenia symptoms and the way it modifies the treatment and prognosis of the illness.

Review of some articles published in Mental Health journals such as “Salud Mental” and “Actas Españolas de Psiquiatría”.

Some studies about psychotic patients have determined 15% as the average of comorbidity of OCD and schizophrenia. The probability of having OCD is six times bigger if there is psychotic pathology associated.

The fact that obsessive and psychotic symptoms get together in some patients shades the prognosis bringing more negative symptoms, more depressive humor, a larger cognitive impairment, more resistance to treatment and more relapses than we can observe in OCD and schizophrenia isolated.

The pharmacological treatment usually consists in neuroleptic plus anti-obsessive drugs, together with cognitive-behavioral therapy. Sometimes, when there is a very bad evolution, it is required to consider psychosurgery as one necessary option, even though its use in this context is not much widespread.

The simultaneous presence of OCD and schizophrenia is more common than we could expect only by chance and makes the prognosis worse, being difficult to find a truly effective treatment.

The authors have not supplied their declaration of competing interest.