How Do Insulinlike Growth Factors Work?

Insulin-like growth factors (IGFs) are a recombinant form of human IGF-1 used for long-term treatment of growth failure in children with severe primary IGF-1 deficiency and to treat autosomal recessive disorder, Laron syndrome (LS) also known as growth hormone (GH) insensitivity. IGF-1 is an important growth hormone that promotes the effect of pituitary GH protein and shows GH independent growth-stimulating effect.

LS is characterized by a deficiency of IGF-1 production. Low levels of IGF-1 may be caused because of mutations in GH receptors in the liver, and these receptors become unresponsive to GH. LS is a very rare condition and children affected with LS present with the following:

• Short stature
• Craniofacial abnormalities
• Micropenis in males
• Low blood sugar

Mecasermin is approved by the U.S Food and Drug administration for the treatment of LS in children. It is used as replacement therapy in children with primary severe IGF-1 deficiency GH receptor mutations causing unresponsiveness toward GH.

IGFs are given as injectables (subcutaneous) to treat primary severe IGF-1 deficiency and LS in children.

Side effects of IGF may include:

• Hypoglycemia
• Dizziness
• Headache
• Cardiac murmurs
• Thymus enlargement
• Tonsil enlargement
• Muscle weakness
• Ear infections
• Skin rash
• Convulsions
• Anaphylaxis (life-threatening allergic reactions)

The information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

Generic and brand names of IGF drugs include:

• Mecasermin
• Increlex