0.5 mL serum in red top or spun serum separator tube (label accordingly).
Test Description
Baseline (fasted) sample.
Sample Handling:
• 12‑hour fast with one flake of hay left in the stall.
• Draw sample in non‑additive tube or serum separator tube and spin.
Note: If baseline insulin results are normal but insulin dysregulation (ID) is strongly suspected, dynamic testing such as an Oral Sugar Test (OST) is recommended. See code L545.