Endo Lft Monitoring Pegvisomant

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name: endo-lft-monitoring-pegvisomant
description: This skill outlines monitoring of liver function tests (LFTs) during pegvisomant therapy for acromegaly. It recommends obtaining LFTs monthly for the first 6 months and then every 6 months, with consideration of discontinuing pegvisomant if transaminases exceed three times the upper limit of normal.
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# Monitor liver function tests during pegvisomant therapy

## STEP 1 — Gather Information
Collect baseline LFTs (ALT, AST, bilirubin, ALP) before initiating pegvisomant; confirm current pegvisomant prescription for acromegaly and note start date.

## STEP 2 — Rule In / Rule Out
Is the patient currently receiving pegvisomant for acromegaly? If NO, do not apply this skill; if YES, proceed to STEP 3.

## STEP 3 — Classify or Stratify
Determine duration of pegvisomant therapy: <6 months → schedule LFTs monthly; ≥6 months → schedule LFTs every 6 months.

## STEP 4 — Decide
If LFTs are normal (ALT/AST ≤3× ULN), continue pegvisomant and repeat testing per the scheduled frequency; if ALT or AST >3× ULN, hold pegvisomant, evaluate for hepatotoxicity, and consider discontinuation per guideline.

## Clinical Guardrails / Mimics / Pitfalls
Do not rely on bilirubin alone; transaminase elevation is the primary signal. Avoid delaying discontinuation when ALT/AST >3× ULN. Rule out other causes of liver injury (e.g., alcohol, hepatitis, concomitant medications) before attributing changes to pegvisomant.

## Concrete Clinical Example
A 48‑year‑old man on pegvisomant 15 mg daily for 5 months has ALT 55 U/L (ULN 35) → continues monthly; at 9 months ALT 130 U/L (>3× ULN) → pegvisomant held, liver work‑up initiated, and therapy discontinued after confirming drug‑related injury.

**Source:** Acromegaly: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2014, DOI:10.1210/jc.2014-2700