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  • Samples should be taken in the morning, preferably between
    7:00 am – 8:00 am, no later than 10:00 am
  • Have an empty stomach – your last meal should be light and eaten
    12-14 hours before the test
  • In the morning before the test, you can drink a small glass of lightly
    sparking water
  • Be well rested – complete your tests after a night of rest
  • Avoid exercise for approximately 24 hours before blood sampling
    (unless you are an athlete)
  • Just before the test, rest – about 15 minutes in a sitting position
    immediately before the collection
  • If you are taking regular medication, check with your doctor that it will
    not interfere with your test results and whether it is possible to take
    them after the tests
  • Maintain your current diet – do not perform the test while consuming
    heavy meals or fasting
  • Limit the consumption of stimulants (eg coffee, alcohol, cigarettes) 2-3
    days before the test
  • Do not perform the test during menstruation, 2 days before or after
  • In the case of infants and young children, it is permissible to consume
    a light meal before blood collection
  • The exception is the determination of glucose concentration
  • Any supplements and probiotics should be discontinued 4-7 days
    before the test
  • After finishing antibiotic therapy or infection (without antibiotic), wait at least two weeks before performing a blood test


  • You should be on an empty stomach, unless you are pregnant
    where this can be permitted
  • The test lasts around 1-2 hours and requires you to remain in
    the waiting room of the collection centre. You cannot leave the
    collection centre for e.g. shopping, walking, etc., because of the
    effort involved (muscle work) any may adversely affect your
  • You cannot eat, drink or smoke while the test is in progress
  • The test consists of taking blood two or three times and
    measuring the glucose level in the samples
  • The first collection is performed on an empty stomach, then the
    patient is given a solution of 75 g of glucose to drink (minimum
    200 ml)
  • After 1 and / or 2 hours, depending on the instructions, more blood samples are taken. For children, the adjustment of glucose dosage
    is indicated by the doctor in relation to the age and the weight
    of the child.


  • Maintain a moderate, normal diet and drinking plenty of fluids
  • Avoid excessive physical exertion which may cause it to affect the urine or to increase its concentration proteins and ketone bodies.
  • Abstain from sexual intercourse in the day preceding the study
  • Thoroughly wash the urethral area with warm water, without abrasive or harsh cleansers
  • Avoid the tests within 2 days before and after menstruation
  • The urine sample is collected in a clean disposable container, preferably sterile, immediately after waking up

The urine sample should be delivered to the laboratory as soon as possible. Within 2 hours when the sample is in storage at room temperature or within 4 hours when stored at 2-8 ° C.


  • The bladder must be completely evacuated before collecting a stool sample
  • Prepare a sterile plastic container with a screw cap and spatula (available from a pharmacy)
  • Collect faeces in a disposable container
  • Using a spatula from a sterile container, take a sample from 5 different places and place it in the container
  • Close the container tightly, protect it against damage and tie it in a foil bag
  • Regardless of the size of the sample, remember that the faeces are collected from several places, so that it contains pathological material (mucus, blood, etc.)

The stool sample should be delivered to the laboratory within 2-3 hours.
If this is not possible, store the material at a temperature of 2-8 ° C and deliver within 24 hours from collection. Up to 2 hours when the sample
is stored at room temperature for up to 4 hours when stored below room temperature.


When you do not follow the above-mentioned guidelines that tell you how to prepare for the test laboratory — THIS WILL DISADVANTAGE YOU


A high fat diet can increase triglycerides (TG) levels in the blood. A high-protein diet can increase the concentration of ammonia, urea, uric acid and total protein in the serum, whilst low-protein works the opposite way.


Refrain from strenuous exercise for 48 hours before the test. Physical activity lowers glucose levels, cholesterol and triglycerides, and increases the activity of creatinine kinase, the concentration of uric acid, hormones and the amount of proteins.


If possible, medications (including vitamin C) should be taken after the sample is collected. Diagnostics will not be performed

if you take, for example, iron preparations (inadequate result).  Caffeine contained in coffee before the test increases the concentration of fatty acids, glucose and hormones.


Consumption within 48 hours before the test, among other things, affects the level of GTTP (hormone used in the diagnosis of cholestasis, liver cancer). In addition, it causes a temporary increase in the volume of erythrocyte.

The above guidelines are general guidelines and any diagnostic laboratory may have its own rules for collecting material for testing.