There are many factors that determine the cost of a lab test, including the type of test, where the test is performed, and if you have insurance coverage. When prescribed by a doctor, testing is often covered if you have insurance, but you may still have a copay or deductible. There can also be fees charged by the technicians who draw your blood.

Typically, a blood sample is taken by inserting a needle into a vein, usually in your arm. Before your blood is drawn, an elastic band is tied around your upper arm to increase blood in the veins, and the puncture location is wiped clean with an antiseptic. A blood draw using a needle may cause a temporary sting. The blood draw normally lasts for less than a minute. Sometimes a blood sample is collected by puncturing the tip of a finger and drop(s) of blood are collected onto a test pad or filter paper, or into a small tube.

Most urine samples are collected by having you urinate into a clean container provided by the lab. One to two ounces of urine is typically needed for testing, and a sufficient sample is required for accurate results. Urine samples usually can be collected at any time, but a first morning sample may be requested because it is more concentrated and more likely to detect abnormalities. For tests requiring a 24-hour urine, all urine produced for 24 hours is collected at home and put into a large container that must be refrigerated during the collection process.
To collect urine for a urinalysis, you may be asked to collect a “clean-catch” urine sample. To keep the sample from becoming contaminated by bacteria, cells, or fluids from outside the urinary tract, it is important to clean the genital area before collecting the urine. You will be given instructions on how to clean the genital area and void a bit of urine first before collecting the sample into the container. Collecting the urine sample may be awkward but it is not in itself uncomfortable. (An infection, however, can create a burning sensation during urination.)

Most tests do not require any special preparation. Others, however, may require you to fast or avoid specific foods or take other steps in advance of the test. You can read the test articles on this site and find the sections titled “Test Preparation?” or “Before the Test” for test specific information. Always follow carefully any instructions you are provided by your healthcare provider and/or the lab that will perform your test.

The results of some tests are intended to be interpreted when you have fasted prior to your sample being collected. Examples include lipid panels and glucose tests. When fasting, drinking only water is permitted. If you do not fast, the results may be affected and/or may not be interpreted correctly. Sometimes your blood sample may be drawn when you have not fasted, and this information is noted on your records. Be sure to follow any instructions you are given and tell the person drawing your blood whether or not you have fasted.

Follow any instructions provided to you by your healthcare provider or the lab that will perform your test. While fasting, you usually are allowed water but should not drink anything else, including coffee, before your sample is collected. Caffeine and other ingredients in coffee can affect the results of some tests.

Some tests are affected by diet, medications and supplements. Follow any test preparation instructions from your healthcare provider or the lab that will perform your test. For some tests, you may need to avoid certain medications before your sample is collected, but you should never discontinue your prescribed medications without first consulting with your healthcare provider. For other tests, you may need to avoid certain foods. An example is creatinine, which can be affected by eating cooked meat prior to your test.