Since 90862 is a psyciatric CPT code, I would try to find out if they are limited to psychiatrists only with a few payors before I billed them. I found a few sources for information for documentation requirements that are helpful in protecting your physician in case of an audit by MCR or a commercial payor.
Source #1:
http://www.doc-txt.com/CPT-90862.pdf
CPT code 90862, Pharmacologic management, including prescription, use, and review of medication with no more than minimal medical psychotherapy:
Please refer to the appropriate CPT code book for the date of services provided. This code is not intended to be used for the actual administration of medication, nor is it intended to be used for observation of the patient taking an oral medication. Administration and supply of oral medication is a non-covered service. Nor is it intended to refer to a brief evaluation of the patientÕs status or simple dosage adjustment of long term medication. The code refers to the in-depth management of psychopharmacologic agents which are potent medications with frequent serious side effects, and represents a very skilled aspect of patient care.
Source #2:
http://www.dss.mo.gov/mhd/providers/pdf/bulletin32-33_2010feb17.pdf
Hope that helps.