Before discussing currently accepted treatments for contamination obssessive-compulsive (OC) disorder, let’s cover treatments that should be avoided (but unfortunately are still used by some providers).
These treatments may be helpful for other problems, but the weight of evidence suggests that for contamination OC (and other forms of OCD), these should be avoided.

Systematic desensitization: The functional component of this treatment involves relaxation in association with feared images and objects. Although this approach is of some value for other anxiety conditions, it is not advisable for contamination OC. One of the clearest reasons is that most people receiving this treatment find they cannot engage in relaxation exercises when they are ‘in the moment’ of their co...

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