After proper identification is made, the patient should be asked if diet restrictions were followed and if the patient is taking any medications. Smoking, chewing gum (which can contain sugar), or chewing tobacco should also be noted, as certain analytes may be affected. Capillary blood collection may be difficult to obtain from chronic smokers because they have impaired circulation in the fingertips.
If diet restrictions are not followed or if the patient is taking medications, the physician should be consulted before going any further since the results may be inaccurate. Some of the test results affected include glucose, triglycerides, insulin, and iron, among others.
