The normal range of serum lactose acid dehydrogenase or LDH is 140 to 280 units per liter, according to WebMD. However, the range may not be constant in all laboratories.
LDH refers to an enzyme that facilitates energy production in the body, states WebMD. Damage to the body cells results in an elevated level of LDH in the blood.
Doctors determine the level of LDH through a sample blood test, as WebMD reports. Aside from diagnosing conditions such as anemia and lung and liver diseases, the test enables doctors to track the progress of chemotherapy in the treatment of lymphoma.