Treatment of MCADD is mainly preventive, by avoiding fasting and other situations where the body relies on fatty acid oxidation to supply energy.

MCADD presents in early childhood with hypoketotic hypoglycemia and liver dysfunction, often preceded by extended periods of fasting or an infection with vomiting.

[4] The enzyme medium-chain acyl-CoA dehydrogenase (MCAD) is responsible for the dehydrogenation step of fatty acids with chain lengths between 6 and 12 carbons as they undergo beta-oxidation in the mitochondria.

This oxidation typically occurs during periods of extended fasting or illness when caloric intake is reduced, and energy needs are increased.

Some mutations, identified through newborn screening programs and associated with higher residual enzyme activity have not been seen in individuals with clinical symptoms of MCADD.

[2] Clinically, MCADD or another fatty acid oxidation disorder is suspected in individuals who present with lethargy, seizures, coma and hypoketotic hypoglycemia, particularly if triggered by a minor illness.

[3] In areas with expanded newborn screening using tandem mass spectrometry (MS/MS), MCADD is usually detected shortly after birth, by the analysis of blood spots collected on filter paper.

[3] Urine organic acid analysis by gas chromatography-mass spectrometry (GC-MS) will show a pattern of dicarboxylic aciduria with low levels of ketones.

[7] MCADD and other fatty acid oxidation disorders have been recognized in recent years as undiagnosed causes of sudden infant death syndrome.

[8][9] As with most other fatty acid oxidation disorders, individuals with MCADD need to avoid fasting for prolonged periods of time.

[3] The duration of fasting for individuals with MCADD varies with age, infants typically require frequent feedings or a slow release source of carbohydrates, such as uncooked cornstarch.

[10] Individuals with MCADD should have an "emergency letter" that allows medical staff who are unfamiliar with the patient and the condition to administer correct treatment properly in the event of acute decompensation.