Question: Missouri Subscriber Answer: Since there was a supervising physician present, and the NP was following an established plan of care in the office suite, you can report the service incident-to the physician. File the claim under the supervising physician's national provider identifier (NPI) number rather than the NP's. (This action will net the practice 100 percent reimbursement for the codes; billing under the NP's NPI will result in a 15 percent pay reduction.) On the claim, report the following: • 90772 (Therapeutic, prophylactic or diagnostic injection [specify substance or drug]; subcutaneous or intramuscular) for the Xolair injection. (Some payers will accept a chemotherapy administration code for Xolair injections. If the payer considers Xolair chemotherapy, report 96401 [Chemotherapy administration, subcutaneous or intramuscular; non-hormonal anti-neoplastic] instead.) • 493.00 (Extrinsic asthma; unspecified) linked to 90772 to indicate the medical necessity for the Xolair injection. • J2357 (Injection, omalizumab, 5 mg) x 60 for the supply of Xolair