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G340
G340 – Histamine test to include a control cold pressor test
OHIP Diagnostic & Therapeutic Procedures Code — DIAGNOSTIC AND THERAPEUTIC PROCEDURES · Schedule of Benefits
G340 is a diagnostic test listed under the Endocrinology and Metabolism subsection of Diagnostic and Therapeutic Procedures. The service involves a histamine test that must include a control cold pressor test. Like all insured services, it is subject to the common elements outlined in the General Preamble (, ).
When to Use
- Use G340 specifically when performing a histamine provocation test to investigate suspected pheochromocytoma or autonomic dysfunction.
- Ensure the procedure includes the mandatory cold pressor control test; if the cold pressor test is omitted, the service is not eligible for G340 billing.
Common Pitfalls
- Billing G340 on the same day as an assessment (e.g., A007 or A005) will result in a rejection, as the General Preamble prohibits concurrent billing of diagnostic procedures and assessments.
- Submitting G340 without clear documentation of the cold pressor control component is a common trigger for post-payment audit recovery.
Billing Tips
- If the patient requires a formal consultation regarding the test results, schedule the consultation on a separate day to ensure both the G340 and the consultation fee are paid.
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