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Information relating to specific disease areas aligned to Pfizer’s portfolio and other resources designed for Pfizer medicines.

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Information on how to access Genotropin® (somatropin, rbe) prescribing information and adverse event reporting can be found at the bottom of the page.

Genotropin efficacy in Prader-Willi Syndrome

Genotropin is indicated for the improvement of growth and body composition in children with Prader-Willi Syndrome (PWS).  The diagnosis of PWS should be confirmed by appropriate genetic testing. 

​​​​​​​Genotropin has a proven, favourable effect on growth and body composition in PWS.1,2

Genotropin efficacy in Prader-Willi syndrome

Improvement in height and body composition1

Improvement in height and BMI standard deviation score (SDS) in children with PWS during 5 years of Genotropin (0.033 mg/kg/day) treatment 1

Improvement in height and body composition1​​​​​​

Improvement in height and BMI standard deviation score (SDS) in children with PWS during 5 years of Genotropin (0.033 mg/kg/day) treatment1

Adapted from Lindgren et al, 19991

Study methods

A controlled, randomised growth hormone (GH) treatment study conducted in 29 pre-pubertal children (3–12 years) with PWS. Height and BMI SDS data was reported from follow up of 9 Swedish children treated with 0.033 mg/kg/day GH, initially for 2 years. GH treatment was stopped for 6 months and thereafter restarted at the same dose for the remainder of the study duration. Values are means ± standard deviation (SD).


Dosage recommendations in Prader-Willi Patients


mg/kg body weight dose per day

​​​​​​​mg/m2 body surface area dose per day

Prader-Willi Syndrome



Please refer to the Summary of Product Characteristics for full information before prescribing Genotropin


Adverse Events in the long-term treatment of Children with Growth Disturbance due to Prader-Willi sydrome

Long-term Treatment and Improvement of Body Composition of Children with Growth Disturbance due to Prader-Willi Syndrome

System Organ Class

Very Common ≥ 1/10

Common ≥ 1/100 to <1/10

Uncommon ≥ 1/1,000 to <1/100

Rare ≥ 1/10,000 to <1/1,000

Very Rare <1/10,000

Not Known (cannot be estimated from available data)

Neoplasms Benign, Malignant and Unspecified (including cysts and polyps)


Metabolism and Nutrition Disorders

Type 2 diabetes mellitus

Nervous System Disorders


Benign intracranial hypertension

Skin and Subcutaneous Tissue Disorders




Musculoskeletal, Connective Tissue and Bone Disorders


Musculoskeletal stiffness*

General Disorders and Administration Site Conditions

Oedema peripheral*

Face Oedema*

Injection site reaction$


Blood cortisol decreased

*In general, these adverse effects are mild to moderate, arise within the first months of treatment, and subside spontaneously or with dose-reduction. The incidence of these adverse effects is related to the administered dose, the age of the patients, and possibly inversely related to the age of the patients at the onset of growth hormone deficiency.
** Adverse Drug Reactions (ADR) identified post-marketing.
$ Transient injection site reactions in children have been reported.
‡ Clinical significance is unknown
† Reported in growth hormone deficient children treated with somatropin, but the incidence appears to be similar to that in children without growth hormone deficiency.

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NICE technology appraisal guidance

Find out more about NICE’s technology appraisals on the use of somatropin

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Endocrine helpline 

Our dedicated nurse team are on hand to support patients being treated with Genotropin and healthcare professionals who have Genotropin patients

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Abbreviations: PWS, Prader-Willi Syndrome; SDS, standard deviation score; BMI, body mass index; GH, growth hormone; SD, standard deviation
  1. Lindgren, A.C., Ritzen, E.M. and collaboration with the Swedish National Growth Hormone Advisory Group, 1999. Acta Paediatrica, 88, pp.109-111.
  2. Genotropin Summary of Product Characteristics. Accessed here.
PP-GEN-GBR-1071. April 2021

Starter kits

A choice of personalised starter kits is available to child and adult Genotropin patients to make sure they get off to a good start with their treatment

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The Genotropin Delivery portfolio

Learn more about the 3 devices available for Genotropin patients

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Pfizer offers a range of homecare and patient support services to Genotropin patients

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PP-PFE-GBR-2688. December 2020