They are also used, with good reason in precocious puberty
Their use in precocious puberty is being questioned, partly because of the impairment of brain function.
This this article looking at blockers use for girls with precocious puberty - suggests girls may see a 7 or 8 point drop in IQ.
Gonadotropin releasing hormone agonists (GnRHas) have been found to impair memory in adults, so the study by Wojniusz et al. (2016) on the possible cognitive effects of these drugs on children treated for idiopathic central precocious puberty (CPP) represents an important contribution to research in this area.
Recent findings that GnRHas increase depression symptoms and slow reaction time in healthy women, and reduce long-term spatial memory in sheep underline the importance of the research that Wojniusz et al. have undertaken.
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Any findings which indicate that GnRHas cause a decline, even a modest decline, in IQ are likely to be of considerable interest to patients and their parents. It is a factor that they may well want to consider in deciding whether or not to take the drug. They may, for example, wish to consider the possible effect of GnRHas on a child's school and exam performance. In this respect it can be noted that 2 of the treated girls had been held back a year at school.
The question of whether a drop in IQ of around 8 points has clinical significance must also be considered in the context of the uncertain benefits of GnRHa treatment for CPP. The ability of GnRHas to increase final height has not been confirmed by randomized controlled trials. Where girls with CPP experience psychosocial difficulties, providing support rather than drugs may be the most appropriate response.