Glucose-galactose malabsorption

Glucose-galactose malabsorption (GGM) is a rare inherited condition where the small intestine cannot properly absorb two simple sugars — glucose and galactose — from food. This happens because a protein called SGLT1, which normally acts like a doorway to carry these sugars from the gut into the bloodstream, does not work correctly. When glucose and galactose cannot be absorbed, they stay in the intestine and draw water in, causing severe, watery diarrhea. This condition is also sometimes called congenital glucose-galactose malabsorption or monosaccharide malabsorption. Symptoms begin within the first days of life, as soon as a newborn starts feeding on breast milk or standard formula — both of which contain lactose, a sugar that breaks down into glucose and galactose. The diarrhea is so severe and watery that it can quickly lead to dangerous dehydration, weight loss, and a build-up of acid in the blood (acidosis). Without prompt treatment, this condition can be life-threatening in newborns. The good news is that this condition can be managed effectively with a strict diet. By removing all sources of glucose and galactose from the diet and replacing them with fructose-based formula and foods, symptoms can be completely controlled. Most children who are diagnosed early and follow the diet carefully can grow and develop normally. Over time, some people with GGM develop a limited ability to tolerate small amounts of glucose and galactose, especially as they get older.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Bring these to your next appointment

• Q1.Which specific foods and ingredients must we completely avoid, and are there any hidden sources of glucose or galactose we might not think of?,How do we ensure our child gets all the nutrients they need on a fructose-based diet, and should we use any supplements?,Will my child's ability to tolerate glucose or galactose improve as they get older, and how will we know if it does?,What are the warning signs that my child has accidentally eaten something they shouldn't, and when should we go to the emergency room?,Should we test other family members, including siblings, for this condition?,What long-term complications should we watch for, such as kidney stones, and how often should we have check-ups?,Are there any clinical trials or new treatments being studied that our family should know about?

Common questions about Glucose-galactose malabsorption

Related conditions

Other rare diseases commonly researched alongside Glucose-galactose malabsorption.

• Congenital sucrase-isomaltase deficiency→
• Fanconi-Bickel syndrome→
• Galactosemia→
• Hereditary fructose intolerance→