Failure to thrive may be caused by medical problems or factors in the child's environment, such as abuse or neglect.

There are many medical causes of failure to thrive. These include:

• Problems with genes, such as Down syndrome
• Organ problems
• Hormone problems
• Damage to the brain or central nervous system, which may cause feeding difficulties in an infant
• Heart or lung problems, which can affect how nutrients move through the body
• Anemia or other blood disorders
• Gastrointestinal problems that make it hard to absorb nutrients or cause a lack of digestive enzymes
• Long-term (chronic) infections
• Metabolism problems
• Problems during pregnancy or low birth weight

Factors in the child's environment include:

• Loss of emotional bond between parent and child
• Poverty
• Problems with child-caregiver relationship
• Parents do not understand the appropriate diet needs for their child
• Exposure to infections, parasites, or toxins
• Poor eating habits, such as eating in front of the television and not having formal meal times

Many times, the cause cannot be determined.

Children who fail to thrive do not grow and develop normally as compared to children of the same age. They seem to be much smaller or shorter. Teenagers may not have the usual changes that occur at puberty.

Symptoms of failure to thrive include:

• Height, weight, and head circumference do not match standard growth charts
• Weight is lower than third percentile of standard growth charts or 20% below the ideal weight for their height
• Growth may have slowed or stopped

The following may be delayed or slow to develop in children who fail to thrive:

• Physical skills, such as rolling over, sitting, standing and walking
• Mental and social skills
• Secondary sexual characteristics (delayed in adolescents)

Babies who fail to gain weight or develop often lack interest in feeding or have a problem receiving the proper amount of nutrition. This is called poor feeding.

Other symptoms that may be seen in a child that fails to thrive include:

• Constipation
• Excessive crying
• Excessive sleepiness (lethargy)
• Irritability

Your health care provider will perform a physical exam and check the child's height, weight, and body shape. Parents will be asked about the child's medical and family history.

A special test called the Denver Developmental Screening Test may be used to show any delays in development. A growth chart outlining all types of growth since birth is created.

The following tests may be done:

• Complete blood count (CBC)
• Electrolyte balance
• Genetic testing
• Hemoglobin electrophoresis to check for conditions such as sickle cell disease
• Hormone tests, including thyroid function tests
• X-rays to determine bone age
• Urinalysis

Treatment depends on the cause of the delayed growth and development. Delayed growth due to nutritional problems can be helped by showing the parents how to provide a well-balanced diet.

Do not give your child dietary supplements such as Boost or Ensure without talking to your provider first.

Other treatment depends on how severe the condition is. The following may be recommended:

• Increase the number of calories and amount of fluid the infant receives
• Correct any vitamin or mineral deficiencies
• Identify and treat any other medical conditions

The child may need to stay in the hospital for a little while.

Treatment may also involve improving the family relationships and living conditions.

Normal growth and development may be affected if a child fails to thrive for a long time.

Normal growth and development may continue if the child has failed to thrive for a short time, and the cause is determined and treated.

Permanent mental, emotional, or physical delays can occur.

Contact your provider for an appointment if your child does not seem to be developing normally.

Regular checkups can help detect failure to thrive in children.

Growth failure; FTT; Feeding disorder; Poor feeding

Marcdante KJ, Kliegman RM, Schuh AM. Failure to thrive. In: Marcdante KJ, Kliegman RM, Schuh AM, eds. Nelson Essentials of Pediatrics. 9th ed. Philadelphia, PA: Elsevier; 2023:chap 21.

Srinath A, Rudolph JA. Nutrition and gastroenterology. In: Zitelli BJ, McIntire SC, Nowalk AJ, Garrison J, eds. Zitelli and Davis' Atlas of Pediatric Physical Diagnosis. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 11.

Updated by: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.