Getting accurate blood test results starts with good preparation. Follow these tips to help your labs give the best picture of your health.
Before Your Appointment
- Fasting (12 hours, if instructed): Water is allowed (and encouraged). No food, coffee, tea, gum, or mints.
- Medications: Take as directed by your doctor.
- The day before: Eat your usual balanced meals. Don’t over-restrict or overeat. Limit alcohol, which can affect liver and sugar results. Avoid very intense exercise, which can temporarily change results.
Hydration for Better Lab Results
- Drink water normally the day before and the morning of your test.
- Being hydrated makes your veins easier to find and may improve results like kidney function and electrolytes.
- Aim for 1–2 glasses of water within a couple of hours before your test (unless your doctor told you to restrict fluids).
Why You Shouldn’t Get Routine Labs While Sick
- Illness (cold, flu, or infection) can temporarily raise or lower values such as white blood cells, liver enzymes, kidney function, blood sugar, or cholesterol.
- These changes don’t reflect your normal health.
- Routine labs are best done when you’re feeling well — unless your doctor is testing specifically for the illness or monitoring a problem.
Quick Tips Checklist
- ⏰ Fast 8–12 hours (unless told otherwise)
- 💧 Drink water (stay hydrated)
- 💊 Take medications as directed
- 🍽️ Eat normally the day before; avoid alcohol
- 🏃 Avoid heavy exercise just before labs
- 🤒 Reschedule routine labs if you’re sick
Remember
Good preparation = more accurate results = better care decisions. If you’re unsure about fasting, hydration, or medications, ask your healthcare provider before your test.
