Classic Galactosemia (GALT)



Classic galactosemia (GALT) is an inherited condition in which the body is unable to properly digest galactose, a sugar found in all foods containing milk. If a baby with GALT eats galactose, undigested sugars build up in the blood rather than being used for energy. If GALT is left untreated, it can cause seizures, serious blood infections, liver damage, or even death. However, when the condition is identified early and proper treatment is begun immediately, individuals with GALT often can lead healthy lives. Galactosemia is a condition with multiple forms, each with different causes and outcomes.  Signs of GALT can appear within a few days after birth and include poor weight gain and growth (failure to thrive), poor feeding and sucking, vomiting, diarrhea, sleeping longer or more often, tiredness, irritability, and low blood sugar (hypoglycemia). Many of these signs may occur when a baby eats foods the body cannot break down.

Condition Type:

Core Conditions


Classic galactosemia (GALT) occurs in 1 in every 30,000 to 60,000 babies. GALT occurs in people of all ethnic groups, but it is most common in people of Irish descent.

More Information for Parents:
Also known as:
  • GALT
  • GALT Deficiency
  • Classic Galactosemia
  • Galactose-1-Phosphate Uridyltransferase Deficiency

Core Conditions