How to Prepare for a Blood Test?

Follow these guidelines for accurate and consistent results.

Schedule your lab test as the first thing in the morning. Blood draws should ideally occur 2-3 hours after waking.

10 days before the test:

  • ⚠️
    Be sure to complete any prescribed courses of antibiotics, antiparasitics, and antifungals as directed by your doctor.
  • 💊
    Start tapering off supplements
    Continue taking any medications prescribed by your doctor, but start tapering off all supplements and non-prescription drugs. This includes electrolytes, vitamins, minerals, powders, recreational drugs, and over-the-counter medications.

3 days before the test:

  • 🏋️‍♂️
    Avoid strenuous activities such as strength training. During this period, engage only in light activities.
  • ⚕️
    If possible, discontinue the use of aspirin and other NSAIDs (such as ibuprofen, etc.).
  • 💊
    You should not be taking any supplements at this point.

Day before the test:

  • 💪
    If you experience moderate muscle soreness, reschedule the test.
  • 🍽️
    Eat a balanced diet, ensuring it's not overly high in proteins, fats, or carbohydrates.
  • ⏳
    Have your last light meal about 12 hours before the blood test, but no less than 10 hours and no more than 15 hours before the test.
  • 🍷
    Do not drink any alcohol.

On the morning of the test:

  • 🥛
    In the morning, drink plain water as follows:
    • 📌
      500 ml of water two hours before the blood test
    • or
    • 📌
      300 ml of water one hour before the blood test.
  • 🚫
    Do not eat anything. Apart from water, do not consume anything else, including coffee, tea, or gum.
  • 🧘‍♂️
    Avoid stress and stimulants, such as work-related stress, cold showers, etc.
  • 🚬
    Nicotine affects blood markers for up to 12 hours. If you smoke, wait until after the test.

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Zsolt Szabo
Zsolt Szabo
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