What are the Symptoms and Treatments for Prader-Willi Syndrome?

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rader-Willi Syndrome (PWS), is a complex genetic disorder that typically causes low muscle tone, short stature, incomplete sexual development, cognitive disabilities, problem behaviors, and a chronic feeling of hunger that can lead to excessive eating and life-threatening obesity.

Symptoms of Prader-Willi Syndrome

Here’s a breakdown of the symptoms by a child’s age:

At Birth:

  • Often breech or caesarean births
  • Lethargy
  • Low muscle tone (called hypotonia)
  • Feeding difficulties (due to poor muscle tone affecting sucking reflex)
  • Difficulties establishing respiration
  • Defects in the reproductive system, called hypogonadism


  • Failure to thrive (continued feeding difficulties)
  • Delayed milestones/intellectual delay
  • Excessive sleeping
  • Eyes not properly aligned with each other, called Strabismus
  • Scoliosis (often not detected at birth)


  • Speech delay
  • Poor physical coordination
  • Hyperphagia (over-eating) from age 2 – 4 years. Note change from feeding difficulties in infancy
  • Excessive weight gain

How is PWS diagnosed?

PWS should be considered when presented with a hypotonic newborn. Genetic testing is recommended for an accurate diagnosis.

Prader-Willi syndrome is often misdiagnosed as Down Syndrome, simply because of the relative frequency of Down Syndrome compared to PWS. Also, marked obesity can occur in Down Syndrome due to behavioral issues. Adding to the confusion, parents of children who already carry a diagnosis of Prader-Willi Syndrome may tell friends, family, and even physicians and nurses that their child has Down Syndrome because more people have heard of that condition.

Treatment of Prader-Willi Syndrome

Prader-Willi Syndrome has no cure. However, several treatments are in place to lessen the conditions symptoms.

Growth hormone replacement therapy improves body composition and increases linear height. During infancy, subjects should undergo therapies to improve muscle tone. Speech and occupational therapy are also recommended. During the school years, children benefit from a highly structured learning environment as well as extra help. Throughout their lives, the subjects food should literally be kept under lock and key, since the largest problem associated with the syndrome is severe obesity.