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Billing code

Z104A — Incision and drainage of perianal abscess or haematoma – local anaesthetic

Drain perianal abscess

Bill for incision and drainage of a perianal abscess or haematoma under local anaesthetic.

Watch for: Under general anaesthetic, bill Z105 instead; add E542 outside hospital.

Code

Z104A

Description

Incision and drainage of perianal abscess or haematoma – local anaesthetic

FHO+ basket

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

Effective date

Apr 1, 2026

Termination date

No end date

Explanation

Updated October 26, 2026

Incision and drainage of a perianal abscess or haematoma under local anaesthetic.

What it covers

Z104 is incision and drainage of an abscess or haematoma in the perianal area when done under local anaesthetic (M1).

The same procedure under general anaesthetic is Z105 (M1).

Billing rules

• Local anaesthetic only; under general anaesthetic bill Z105 (M1).
• Add E542 when performed outside hospital (M1).
• Surgical procedure: age premiums apply for patients under 16, from +10% (age 5–15) up to +30% (under 30 days) (GP64).
• Non-elective and done after hours: ED physicians billing H-codes add E412 (+20%, evenings/weekends/holidays) or E413 (+40%, 00:00–07:00); other physicians add E409 or E410 (GP104).
• FHO: a Schedule 4 office procedure that counts toward the office procedures special payment when done in your office for enrolled patients (Agreement p.94, §8.7).

Often billed with

• E542 in the office (M1).

Related codes: Z105, Z101, Z173, Z174, Z106, E542, Z103

Source: Schedule of Benefits (July 1, 2026), Integumentary System Surgical Procedures, Skin and Subcutaneous Tissue, page M1.

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