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Billing code

G501A — Trh Or Lhrh Test, Per Injection

TRH or LHRH stimulation test

Bill G501 for a TRH or LHRH pituitary stimulation test, claiming the number of injections given.

Watch for: When given as part of an insulin hypoglycemia test, bill G497 instead of G501.

Code

G501A

Description

Trh Or Lhrh Test, Per Injection

FHO+ basket

Not in the FHO+ base rate basket (Schedule 2 or 2B).

Effective date

Apr 1, 2025

Termination date

No end date

Explanation

Updated October 26, 2026

TRH or LHRH stimulation test for pituitary function, billed per injection given.

What it covers

G501 is a TRH or LHRH test, billed per injection (J43).

When TRH and/or LHRH are given as part of an insulin hypoglycemia pituitary function test, that combined test is G497 (J41).

Billing rules

• Billed per injection: claim the number of injections given (J43).
• Payable in addition to a consultation or assessment unless listed as included (J3).
• Includes preparing the patient, doing the test with monitoring afterwards, interpreting results with a written report to the referring provider where appropriate, and follow-up arrangements (J3).
• Marked (+): when the test is the sole reason for the visit, add G700 once per visit. G700 is not payable in hospital, and not when you are also paid a consultation or assessment that day and have a financial interest in the facility (J3).
• For a patient enrolled with a capitation-based group, G700 pays 15% of its fee (J3).

Often billed with

• G700 basic fee-per-visit premium when the test is the only reason for the visit, outside hospital (J3).

Related codes: G497, G493, G513, G700

Source: Schedule of Benefits (July 1, 2026), Diagnostic and Therapeutic Procedures, Endocrinology and Metabolism, page J43; preamble J3.

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