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CPT codes 90846 and 90847: Family psychotherapy is covered by when the primary purpose of such counseling is the treatment of the patient's condition. For example, two situations where FAMILY counseling services would be appropriate are as follows:
Where there is a need to observe the patient's interaction with FAMILY members; and/or where there is a need to assess the capability of and assist the FAMILY members in aiding in the management of the patient.
See CMS Publication 100-3, the National Coverage Determinations Manual, Chapter 1, Section 70.1 via the following link: