National Stroke Foundation

Genotropin (somatropin) injection

The following drug information is obtained from various newswires, published medical journal articles, and medical conference presentations.

Approval Status:

Approved July 2001

Specific Treatments:

Growth failure in children who were born small for gestational age (SGA)

General Information

The FDA has approved Genotropin (somatropin [rDNA origin] for injection) for the long-term treatment of growth failure in children who were born small for gestational age (SGA). The drug is indicated for children who do not achieve catch-up growth by age two.

Small for gestational age (SGA) is a term used to describe an infant who is smaller in size than expected based on the number of weeks of pregnancy. Each year, as many as 12,000 children born SGA do not "catch up" in terms of height by age two. Many of these children remain significantly smaller than their peers and may not reach normal height without medical intervention.

Since August 1995, Genotropin Lyophilized Powder has been approved for the long-term treatment of growth failure in children due to growth hormone deficiency (GHD). The drug is also currently marketed as replacement therapy in adults with a confirmed diagnosis of GHD of either childhood or adult onset. More recently, Genotropin was approved for the treatment of pediatric patients with Prader-Willi Syndrome, a genetically based developmental disability.

Side Effects

Adverse events reported during clinical trials of Genotropin include (but are not limited to) the following:

  • Injection site reactions
  • Headache
  • Edema (fluid retention)
  • Aggressiveness
  • Arthralgia (joint pain)
  • Myalgia (muscle pain)
  • Hair loss

Mechanism of Action

Genotropin Lyophilized Powder contains somatropin [rDNA origin], which is a polypeptide hormone of recombinant DNA origin.

In vitro, preclinical and clinical tests have demonstrated that Genotropin Lyophilized Powder is therapeutically equivalent to human growth hormone of pituitary origin and achieves similar pharmacokinetic profiles in normal adults. In pediatric patients who have growth hormone deficiency (GHD) or Prader-Willi syndrome (PWS), treatment with Genotropin stimulates linear growth and normalizes concentrations of IGF-I (Insulin-like Growth Factor/Somatomedin-C). In adults with GHD, treatment with Genotropin results in reduced fat mass, increased lean body mass, metabolic alterations that include beneficial changes in lipid metabolism, and normalization of IGF-I concentrations. (from Genotropin Prescribing Information)

Additional Information

For additional information on Genotropin, please visit the product web site at