Things that may interfere with
the accuracy of a lab test include:
Not following the instructions for how to
prepare for the test. Some tests, such as a
cholesterol and triglycerides analysis, might require you to
stop eating for at least 12 hours before the test. Other tests, such as a
2-hour postprandial blood sugar, require that you eat
exactly 2 hours before the test.
Some medicines or herbal
treatments. For example, many medicines raise or lower blood sugar levels and
could interfere with blood sugar tests. Birth control pills and some steroids
can raise blood sugar, while some medicines to treat
high blood pressure and
depression can lower it.