Do I need to fast?
Fasting rules depend on the test and on the lab. Each page explains what usually applies and reminds you to confirm the exact window with the collection site.
Prep-first lab testing guides
Prepare for your lab test before you book it
LabPreparation explains the part people get wrong: how to prepare. Every guide covers fasting, collection timing, sample type, and what to bring — in plain language, with no guessing.
- 665 tests explained
- 52 states & territories
- Confidential ordering
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Three questions answered on every page
The directory is organized around the decisions that make or break a collection visit.
When should I collect?
Morning draws are common, and some tests are tied to specific windows. Prep pages cover the timing basics so you can book a slot that fits.
What should I bring?
Photo ID, your order or requisition, a medication list, and water for fasting visits — every guide includes a short checklist you can copy.
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Find your test
Search the directory, or browse the featured prep guides below.
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By location
Prep guides by state
Statewide directories for planning a collection visit.
- PacificAlaskaStatewide prep guides
- SouthwestArizonaStatewide prep guides
- SouthArkansasStatewide prep guides
- PacificCaliforniaStatewide prep guides
- Mountain WestColoradoStatewide prep guides
- New EnglandConnecticutStatewide prep guides
- Mid-AtlanticDelawareStatewide prep guides
- SouthFloridaStatewide prep guides
- SouthGeorgiaStatewide prep guides
- PacificHawaiiStatewide prep guides
- Mountain WestIdahoStatewide prep guides
- MidwestIllinoisStatewide prep guides
Reading
Prep guides & explainers
- Appointment PrepWhat to Bring to a Lab Appointment: A Simple ChecklistA practical checklist for lab day, including identification, your order or requisition…
- Condition-Specific PanelsPreparing for a CBC: What a Complete Blood Count Needs From YouHow to prepare for a complete blood count, whether fasting or hydration matters, what can shift…
- Condition-Specific PanelsPreparing for a Kidney Panel: Hydration, Timing, and MedicationsHow to prepare for kidney function tests, including hydration, protein intake, medication…