The lactate dehydrogenase (LDH) isoenzyme test checks how much of the different types of LDH are in the blood.
A blood sample is needed.
The health care provider may tell you to temporarily stop taking certain medicines before the test.
Drugs that can increase LDH measurements include:
DO NOT stop taking any medicine before talking to your provider.
When the needle is inserted to draw blood, some people feel slight pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.
LDH is an enzyme found in many body tissues such as the heart, liver, kidney, skeletal muscle, brain, blood cells, and lungs. When body tissue is damaged, LDH is released into the blood.
The LDH test helps determine the location of tissue damage.
LDH exists in five forms, which differ slightly in structure.
All of these can be measured in the blood.
LDH levels that are higher than normal may suggest:
There is little risk in having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.