A digoxin test checks how much digoxin you have in your blood. Digoxin is a type of medicine called a cardiac glycoside. It is used to treat certain heart problems.
How the Test is Performed
A blood sample is needed. For information on how this is done, see: Venipuncture
How to Prepare for the Test
Ask your health care provider whether you should take your usual medications before the test.
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing where the needle was inserted.
Why the Test is Performed
The main purpose of this test is to determine the best dosage of digoxin and prevent side effects.
It is important to monitor the level of digitalis medications such as digoxin. That is because the difference between a safe treatment level and a harmful level is small.
In general, normal values range from 0.8 to 2.0 nanograms per milliliter of blood. But some patients may need even lower amounts.
The examples above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean
Abnormal results may mean you are getting too little or too much digoxin.
A very high value could mean that you have or are likely to develop a digoxin overdose (toxicity).
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
- Excessive bleeding
- Fainting or feeling light-headed
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
Pincus MR, Abraham NZ Jr. Toxicology and therapeutic drug monitoring. In: McPherson RA, Pincus MR, eds. Clinical Diagnosis and Management by Laboratory Methods. 22nd ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 23.
Update Date 5/13/2014
Updated by: Michael A. Chen, MD, PhD, Assistant Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.