Key Takeaways
- Understanding galactosemia lactose intolerance seniors genetic disorder is important for seniors and their caregivers.
- Infants with galactosemia may show symptoms in the first few days of life if they eat formula or breast milk that contains lactose.
- Tests to check for galactosemia include:
- People with this condition must avoid all milk, products that contain milk (including dry milk), and other foods that contain galactose, for life.
- More information and support for people with galactosemia and their families can be found at:
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Galactosemia is a condition in which the body is unable to use (
metabolize
) the simple sugar galactose.
What Are the Common Causes and Risk Factors?
Understanding galactosemia lactose intolerance seniors genetic disorder is important for seniors and their caregivers. galactosemia is an inherited disorder. This means it is passed down through families. If both parents carry a nonworking copy of the gene that can cause galactosemia, each of their children has a 25% (1 in 4) chance of being affected with it. This is called autosomal recessive inheritance.
There are 3 forms of the disease:
- Galactose-1 phosphate uridyl transferase (GALT) deficiency: Classic galactosemia, the most common and most severe form
- Deficiency of galactose kinase (GALK)
- Deficiency of galactose-6-phosphate epimerase (GALE)
People with galactosemia are unable to fully break down the simple sugar galactose. Galactose makes up one half of lactose, the sugar found in milk.
If an infant with galactosemia is given milk, substances made from galactose build up in the infant’s system. These substances damage the liver, brain, kidneys, and eyes.
People with galactosemia cannot tolerate any form of milk (human or animal). They must be careful about eating other foods containing galactose.
What Are the Symptoms and Warning Signs?
Infants with galactosemia may show symptoms in the first few days of life if they eat formula or breast milk that contains lactose. They may develop a serious blood infection with the bacteria
E coli
.
Symptoms of galactosemia are:
-
Convulsions
-
Irritability
-
Lethargy
- Poor feeding — baby refuses to eat formula containing milk
- Poor weight gain
- Yellow skin and whites of the eyes (jaundice)
- Vomiting
📖 What Are Exams and Tests?
What Are Exams and Tests?
Tests to check for galactosemia include:
-
Enzyme
activity in the red blood cells
-
Ketones in the urine
-
Prenatal diagnosis by directly measuring the enzyme
galactose-1-phosphate uridyl transferase
-
“Reducing substances” in the infant’s urine, and normal or
low blood sugar
while the infant is being fed breast milk or a formula containing lactose
-
Genetic testing for the gene that causes this disorder
In many states, newborn screening tests check for galactosemia.
Test results may show:
-
Amino acids in the urine
or blood plasma
-
Enlarged liver
-
Fluid in the abdomen
- Low blood sugar
📖 How Is It Treated?
How Is It Treated?
People with this condition must avoid all milk, products that contain milk (including dry milk), and other foods that contain galactose, for life. Read product labels to make sure you or your child with the condition are not eating foods that contain galactose.
Infants can be fed:
- Soy formula
- Another lactose-free formula
-
Meat-based formula or a
protein
hydrolysate formula
Calcium supplements are recommended.
📖 What Are Support Groups?
📖 What Is Outlook (Prognosis)?
What Is Outlook (Prognosis)?
People who are diagnosed early and strictly avoid milk products and other foods that contain lactose can live a relatively normal life. However, mild mental impairment may develop, even in people who avoid galactose.
📖 What Are Possible Complications?
What Are Possible Complications?
These complications can develop:
-
Cataracts
-
Cirrhosis
of the liver
- Delayed speech development
- Irregular menstrual periods, reduced function of ovaries leading to ovarian failure and infertility
-
Mental disability
-
Severe infection with bacteria (
E coli sepsis
) - Tremors (shaking) and uncontrollable motor functions
- Death (if there is galactose in the diet)
📖 When to Contact a Medical Professional?
When to Contact a Medical Professional?
Contact your health care provider if:
- Your infant has galactosemia symptoms
- You have a family history of galactosemia and are considering having children
📖 How Is It Prevented?
How Is It Prevented?
It is helpful to know your family history. If you have a family history of galactosemia and want to have children,
genetic counseling
will help you make decisions about pregnancy and prenatal testing. Once the diagnosis of galactosemia is made, genetic counseling is recommended for other members of the family.
Many states screen all newborns for galactosemia. If the newborn test shows possible galactosemia, they should contact the child’s provider right away for advice about giving their infant milk products. They should also ask the provider about having blood tests that can be done to confirm a diagnosis of galactosemia.
Galactose-1-phosphate uridyl transferase deficiency; Galactokinase deficiency; Galactose-6-phosphate epimerase deficiency; GALT; GALK; GALE; Epimerase deficiency galactosemia; GALE deficiency; Galactosemia type III; UDP-galactose-4; Duarte variant
-
Galactosemia
Berry GT. Classic galactosemia and clinical variant galactosemia. 2000 Feb 4 [updated 2021 Mar 11]. In: Adam MP, Feldman J, Mirzaa GM, Pagon RA, Wallace SE, Amemiya A, eds.
GeneReviews
[Internet]. Seattle, WA: University of Washington. PMID: 20301691
pubmed.ncbi.nlm.nih.gov/20301691/
.
Bonnardeaux A, Bichet DG. Inherited disorders of the renal tubule. In: Yu ASL, Chertow GM, Luyckx VA, Marsden PA, Skorecki K, Taal MW, eds.
Brenner and Rector’s The Kidney
. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 44.
Hijazi G, Kishnani PS. Defects in metabolism of carbohydrates. In: Kliegman RM, St. Geme JW, Blum NJ, et al, eds.
Nelson Textbook of Pediatrics
. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 107.
Pearl PL, DiBacco ML, Gibson KM. Inborn errors of metabolism and the nervous system. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds.
Bradley and Daroff’s Neurology in Clinical Practice
. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 91.
Updated by: Anna C. Edens Hurst, MD, MS, Associate Professor in Medical Genetics, The University of Alabama at Birmingham, Birmingham, AL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
-
Carbohydrate Metabolism Disorders
Frequently Asked Questions
Key Takeaways
People with this condition must avoid all milk, products that contain milk (including dry milk), and other foods that contain galactose, for life.
What Are the Common Causes and Risk Factors?
What Are the Symptoms and Warning Signs?
E coli
. Symptoms of galactosemia are:
Convulsions
Irritability
Lethargy
Poor feeding — baby refuses to eat formula containing milk
Poor weight gain
Yellow skin and whites of the eyes (jaundice)
Vomiting
📖 What Are Exams and Tests?
What Are Exams and Tests?
Enzyme
activity in the red blood cells
Ketones in the urine
Prenatal diagnosis by directly measuring the enzyme
galactose-1-phosphate uridyl transferase
“Reducing substances” in the infant’s urine, and normal or
low blood sugar
while the infant is being fed breast milk or a formula containing lactose
Genetic testing for the gene that causes this disorder
In many states, newborn screening tests check for galactosemia. Test results may show:
Amino acids in the urine
or blood plasma
Enlarged liver
Fluid in the abdomen
Low blood sugar
📖 How Is It Treated?
How Is It Treated?
Soy formula
Another lactose-free formula
Meat-based formula or a
protein
hydrolysate formula
Calcium supplements are recommended.
About the Author: This article was researched and written by the SilverWell Hub editorial team. It was medically reviewed by Dr. Sarah Mitchell, MD, Geriatrics.
Sources: This article is adapted from MedlinePlus, a service of the National Library of Medicine.
Disclaimer: This information is for educational purposes only. See our full Medical Disclaimer.
Published: July 24, 2026 | Next review: January 2027
