Accelerating Treatment for Obsessive-Compulsive Disorder

Enhancing Exposure with Medications

Some Medications Improve Learning

The hope is that combined medication and CBT results in an additive or synergistic effect. However, the reality is that adding medications that reduce anxiety, such as SSRIs, to exposure and ritual prevention (Ex/RP) treatment does not improve outcome, and anti-anxiety medications like benzodiazapines may actually interfere with therapy. Such medications may interfere directly with extinction learning or patients may attribute success to the medication (rather than the therapy or their own efforts) and then start avoiding things again while discontinuing medication. However, adding medications that improve memory (at least for extinction learning) may improve exposure-based treatment efficacy. This is facilitated by a growing class of drugs referred to as “cognitive enhancers.” Examples of cognitive enhancers include: D-cycloserine, yohimbine hydrochloride, and methylene blue. The most researched compound in this class to date is D-cycloserine or DCS.

D-cycloserine is Safe and Effective

DCS is an antibiotic originally used in the treatment of tuberculosis. The high doses used in the treatment of tuberculosis (500-1000 mg/day) came with a fairly negative side-effect profile. However, one side-effect noted was improved memory. Due to the memory enhancing effects, DCS was investigated as a treatment for Alzheimer’s disease and schizophrenia. Unfortunately, people develop rapid tolerance to the positive memory effects of DCS. Thus, DCS is not useful for long-term administration to improve memory. Rather, DCS can be used for discrete learning episodes for material that is important to remember. In this way, DCS is used to enhance the learning that occurs with exposure-based treatment of OCD. Also, unlike the high doses needed to treat infection, much lower doses are effective for enhancing memory (as little as 50 mg). At this dose, significant side-effects are not reported.

The Need for Speed

Exposure therapy worked 2.3 times faster when D-cycloserine was added.

DCS augmented exposure therapy has now been investigated across many anxiety disorders, including OCD, showing a small to large advantage over exposure therapy with placebo. Initially, several studies investigating the use of D-Cycloserine to improve exposure-based OCD treatment yielded somewhat inconsistent results. But upon closer examination, it appears that DCS is most effective at increasing the speed/efficiency of Ex/RP when administered very close to the time of the exposure sessions (1 hour before or after) and that the benefit seems to decrease over repeated sessions. This is consistent with the finding that people quickly develop a tolerance to DCS and the potential for floor effects given the already potent efficacy of Ex/RP over the usual 17 sessions. One randomized controlled trial of 22 patients conducted by researchers at Harvard and Yale found that patients given DCS with their Ex/RP therapy improved 2.3 times faster than those given a placebo. Although promising, DCS is still not in widespread use in clinical practice. Nonetheless, for many people DCS may help reduce costs, drop-out rates, and speed up therapeutic progress in Ex/RP.

Accelerate Your Treatment

In summary, medications like DCS that improve memory (cognitive enhancers) administered immediately before or after initial exposure sessions in Ex/RP may speed response. Contact us if you would like to arrange an appointment to speak to a knowledgable mental health provider about your OCD treatment options. Our skilled psychiatrist can prescribe D-cycloserine, if indicated.

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Chasson, G. S., Buhlmann, U., Tolin, D. F., Rao, S. R., Reese, H. E., Rowley, T., & ... Wilhelm, S. (2010). Need for speed: Evaluating slopes of OCD recovery in behavior therapy enhanced with D-cycloserine. Behaviour Research And Therapy, 48(7), 675-679. doi:10.1016/j.brat.2010.03.007

Williams, M. T., Davis, D. M., Powers, M., & Weissflog, L. O. (2014). Current Trends in Prescribing Medications for Obsessive-Compulsive Disorder: Best Practices and New Research. Directions in Psychiatry, 34 (4), 247-261.