Q:What are the risks of my child taking growth hormone replacement drugs, particularly Genotropin? L M W.......
Growth hormones are the medical solution for children who aren't growing in line with growth charts. Genotropin is a synthetic growth hormone identical in terms of the amino acids and their sequence to the human growth hormone somatropin produced by the pituitary.
This synthetic version, given by injection, is reputed to stimulate skeletal growth in children with growth hormone deficiency. It's supposed primary indication is children who secrete inadequate amounts of their own growth hormone; in practice, it's given to any child at the low end of the growth charts whose parents are starting to get nervous about it.
As with any other exogenous hormone (made outside our bodies) Genotropin comes with a number of side effects. The American Physicians' Desk Reference warns that human growth hormone may induce insulin resistance, so that any patient on this drug must be monitored regularly for glucose intolerance. It can also cause hypothyroidism (underactive thyroid), which, if untreated, can interfere with action of the drug.
It's known that patients with disorders of the endocrine system often have a higher incidence of slipped capital femoral epiphysea (fracture of the growth plate of the thigh bone). This means that any child complaining of hip or knee pain during growth hormone therapy should be immediately evaluated. Hypertension and pressure in the skull with papilledema (swelling of the optic disc), visual changes, headache, nausea and/or vomiting have been reported in a small number of patients treated with growth hormone products, usually during the first eight weeks of therapy, which resolved once the drug was stopped or the dosage lowered.
According to manufacturers Pharmacia & Upjohn, studies have shown that nearly 2 per cent of patients on Gonetropin develop antibodies to the protein in the drug, high levels of which can interfere with growth.
Most worryingly, a small percentage of children given growth hormone have developed leukemia.
Otherwise, the drug can cause rash, inflammation, pigmentation, bleeding, atrophy of fat tissue, headache, blood in the urine and mild hyperglycemia (high blood sugar).
Besides the issue of side effects, there's also the question of whether this drug does any good at all. A recent French study found that the drug failed to restore normal growth to most of the children who used it. It worked best on those with genuinely low levels of growth hormone, although this can be difficult to define with certainty since normal levels of the hormone in growing children constantly alter (BMJ, 1997; 315: 708-13).
Before reaching for such a drastic measure, it might be wise first to rule out anything that could be restricting your child's growth, such as steroids for another condition. It may also be worth being patient, as many children who are undersize in childhood undergo sudden growth spurts and normalize by the time they reach adolescence. Aternatives columnist Harald Gaier has had success in giving undersized children a combination of the amino acid L-pyroglutamic acid, plus the protein body builder Twin labs Amino Fuel 200 and good multivitamins. This combination quickly worked on his own son, who was in the bottom 4 percentile of height at age 8 and quickly shot up to normal.