Faltering weight

There are many possible medical causes of faltering weight in children. These include:

• Problems with genes, such as Down syndrome
• Internal organ problems
• Hormone problems
• Injury to the brain or central nervous system, which may cause feeding difficulties in an infant
• Swallowing problems
• 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
• Kidney disease, such as renal tubular acidosis
• Long-term (chronic) infections
• Food allergies
• Metabolism problems
• Problems during pregnancy or low birth weight

Other factors may include:

• Problems with the child-caregiver relationship
• Parents who don't 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 with faltering weight 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 faltering weight include:

• Height, weight, and head circumference do not match standard growth charts
• Weight is lower than the 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 with faltering weight:

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

Babies who show poor weight gain 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 has a faltering weight include:

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

Your child's health care provider will perform a physical exam and check your child's length or height, weight, BMI, and body shape as part of the initial check-up. Parents will be asked about their child's medical and family history. If your child has undergone any surgery, the provider will ask about your child's surgical 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.

If your child has persistent faltering weight or severe malnutrition, lab testing may be done to find out the cause. Testing is also done if your child has a feeding disorder or shows any additional signs or symptoms.

Tests may include:

• Complete blood count (CBC)
• Comprehensive metabolic panel
• 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
• Endoscopy with biopsy for conditions that cannot be diagnosed without endoscopy

The 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.

Before giving your child dietary supplements such as Boost or Ensure, talk with your child's provider.

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

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

In some cases, your child may need to stay in the hospital for a little while. Feeding therapy may be given to children who have feeding difficulties.

Parents can be advised to keep a food log or record photos or videos of their infants or children while breastfeeding or eating. This will help your provider track your child’s calorie intake and also their feeding patterns.

Talk with your child's provider if you are having financial or other problems that make it difficult to provide healthy nutrition for your child. Your provider can help you find resources to support you and your family.

Normal growth and development may be affected if your child has a faltering weight for a long time.

Normal growth and development may continue if your child has faltering weight for a short time, and the cause is determined and treated.

Permanent mental, emotional, or physical delays can occur.

Contact your child's provider if your child does not seem to be developing normally.

Regular checkups (sometimes called well child visits) can help detect faltering weight in children.

Failure to thrive; Growth failure; FTT; Feeding disorder; Poor feeding

AlShenaiber L, Senerth E, Babatunde I, et al. The impact of socioeconomic status and different treatment modalities on children with faltering weight: technical report. Pediatrics. 2026. PMID: 41833314 pubmed.ncbi.nlm.nih.gov/41833314/.

Diab LK, Gilley SP, Krebs NF. Malnutrition in high-resource settings. In: Kliegman RM, St Geme JW, Blum NJ, et al, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 64.

Kersten HB, Goday PS, Abdelhadi R, et al. Clinical Practice Guideline for diagnosis and management of faltering weight. Pediatrics. 2026. PMID: 41833317 pubmed.ncbi.nlm.nih.gov/41833317/.

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: Charles I. Schwartz, MD, FAAP, Clinical Assistant Professor of Pediatrics, Regional Medical Director of Penn Medicine Primary and Specialty Care, Perelman School of Medicine at the University of Pennsylvania, General Pediatrician at PennCare for Kids, Phoenixville, PA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.