Per CPT Assistant 2/05: Codes 95120-95134 are complete service codes representing the combined supply of antigen plus the allergy injection provided at a single encounter. These codes are used infrequently and are recommended in those cases only where the payer specifically requires them. As explained under CMS Guidelines, Medicare does not allow payment of these codes.
Codes 95145-95170 represent the antigen itself, its preparation, and the physician's determination of concentration and volume required for the planned schedule of injections based on skin testing and patient history. These codes are used to report the supply of antigen prospectively planned to be administered. (In some cases, the patient may not eventually receive the number of planned doses because of reactions or for other reasons. Regardless, it is appropriate to bill the prospectively planned supply of the antigen at the outset of the scheduled treatment.) The number of doses prepared and provided must be specified when reporting these codes. Administration of injections is not included in these codes.
Codes 95115-95117 describe the professional service of administration of allergenic extract -the injection itself- but do not include the actual supply of the allergenic extract that is given. These injection codes may be used by the allergist who bills separately for the injection and for the prospectively prepared supply of allergenic extract (see codes 95144-95170 for reporting supply of the extract). Similarly, the injection codes may be used a by a physician (eg, primary care physician) who administers the allergy injection only, using allergenic extract brought to the office by the patient and previously prepared by the patient's allergist.
We mix and code 95144-95170 at the time of mixing; 95115-95117 at the time of the injection(s).