Medium-Chain acyl-CoA Dehydrogenase Deficiency (MCAD)



Medium-chain acyl-CoA dehydrogenase deficiency (MCAD) is a condition in which the body is unable to break down certain fats. Individuals affected with MCAD are unable to convert some of the fats they eat into energy the body needs to function. Instead, too many unused fatty acids build up in the body. If untreated, MCAD can cause brain damage and breathing problems. However, if the condition is detected early and proper treatment is begun, individuals affected by MCAD can often lead healthy lives. The first signs of MCAD usually begin during infancy or 3 months to 3 years of age. Signs of MCAD include sleeping longer or more often, tiredness, irritability, poor appetite, fever, diarrhea, vomiting, and low blood sugar (hypoglycemia). Many of these signs may occur when a baby eats foods the body cannot break down. Symptoms can be triggered by long periods of time without eating, illnesses, and infections.

Condition Type:

Fatty Acid Oxidation


Medium-chain acyl-CoA dehydrogenase deficiency (MCAD) is estimated to affect 1 out of every 15,000 babies born in the United States. It is more common in people of northern European ancestry.

More Information for Parents:
Also known as:
  • Medium-chain Acyl-CoA dehydrogenase deficiency
  • ACADM deficiency
  • MCADH deficiency

Core Conditions