A new study finds talk therapy for people with post-traumatic stress disorder (PTSD) does not appear to increase the risk of relapse in people with substance use disorders, HealthDay reports.

About one-fourth of people with drug or alcohol use disorders also have PTSD, according to the researchers from Johns Hopkins University. They studied the use of cognitive behavioral therapy, which exposes patients to memories of their trauma. The researchers said patients and health care providers have been reluctant to use cognitive behavioral therapy to treat PTSD in patients with substance use disorders because they are concerned that thinking and talking about traumatic events will cause relapse.

The new study of 44 patients analyzed week-to-week comparisons of cravings for opioids or other drugs before and after therapy sessions, self-reported days of drug use and other distress. There was no increase in patients’ use of opioids or other drugs, or in reported instances of stress after therapy sessions to treat PTSD, the researchers reported in the Journal of Traumatic Stress.