Preparing for a Lab Test

Preparing for a Lab Test

Preparing for a Lab Test

Lab tests are procedures where a healthcare provider takes urine, blood, or other body fluid samples to inform them about your health. Lab tests are often performed to screen or diagnose for a specific condition or disease. These screenings have the potential to diagnose diseases before symptoms occur. Other lab tests can monitor diseases or determine if a treatment you have is adequate. Lab tests can also provide your doctor with general information about your body systems and organs. Our experts on diagnostic dermatopathology in Pittsburgh, PA, explain that you should prepare for any lab test by:

  • Informing your provider about any supplements, vitamins, or medications you take.
  • Closely following your physician’s instructions.
  • Informing the lab tech if you did not precisely follow your physician’s instructions because it can impact your results.

These preparations will ensure reliable and accurate results.

Additional lab test preparations

Many lab tests require nothing more than answering your physician and lab tech’s questions, but there may be test-specific instructions in some situations. For example, fasting is a standard lab test preparation. Fasting means not drinking anything but water or eating overnight or several hours before testing. This is essential because food ingredients and nutrients are absorbed into your blood. Depending on the test, these elements can impact your test results. In addition, fasting length varies by the test, so be sure to confirm the length of fasting with your doctor.

Other test preparations you might encounter include:

  • Abstaining from certain supplements or medications.
  • Abstaining from certain behaviors like sexual activity or strenuous exercise.
  • Avoiding smoking.
  • Not overeating the day before your test.
  • Abstaining from specific drinks and foods, like alcohol, herbal tea, and cooked meats.

Some blood tests require you to drink additional water to keep plenty of fluid in your veins, and your doctor may advise you to drink water 15 to 20 minutes before specific urine screens.

Lab tests requiring special preparation

Fasting is required for many standard lab tests, including:

  • Calcitonin tests
  • Triglycerides tests
  • Cholesterol level tests
  • Blood glucose tests

Other special preparations are required for common lab tests, including:

  • Pap smears- Your doctor may instruct you to abstain from sex, tampon usage, and douching for 24 to 48 hours before testing.
  • 5-HIAA tests- Your doctor may instruct you to abstain from eating certain foods, including eggplant, walnuts, pineapple, banana, and avocado.
  • Fecal occult blood test- Your doctor may instruct you to avoid certain medications or foods.
  • Cortisol tests- You may need to rest for a while before your sample is taken. You also might be instructed to avoid brushing your teeth, drinking, or eating for a certain period before testing.
  • Creatinine tests- Your doctor may instruct you to avoid cooked meats or fast.

Talk to your doctor if you have concerns or questions about any test preparations. It is vital to understand preparation instructions before your test date.

These are some of the lab test preparations you may encounter. Remember to follow instructions closely for reliable and accurate test results. Failure to follow special preparation instructions may lead to inaccurate or inconclusive test results. Contact us today for diagnostic dermatopathology in Pittsburgh, PA.



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