Adverse effects of adult topical androgen use on children

To the Editor: We read with interest the report by Handelsman describing an increase in Australian testosterone prescriptions, including a particular increase in prescribing of topical testosterone gel.1

The topically applied formulation of testosterone has a unique adverse-effect profile because of inadvertent exposure to it via direct skin contact. We report progressive virilisation in a 2-year-old girl who presented in 2011 with an 18-month history of body odour and pubic hair development, associated with her father having administered testosterone gel on his forearms. The child’s virilisation resolved when her father changed his method of androgen administration. He had not been informed of the risk to children of inadvertent androgen exposure, and he did not know the indication for his treatment with testosterone.

Some of the growing population of men who are prescribed testosterone are of childrearing age, and possible paediatric exposure should be considered when selecting an androgen formulation. We are aware of five similar cases nationally, involving virilisation of children due to topical androgen use by their parents on locations such as the anterior chest wall. Inadvertent exposure of children to topical androgens can lead to irreversible skeletal maturation, intrauterine virilisation of unborn children, and significant enlargement of the clitoris in young girls.2,3

Patients should be routinely warned of this potential adverse effect when testosterone gels are prescribed. Furthermore, the Therapeutic Goods Administration should consider imposing a boxed warning for this formulation of testosterone, as occurs in the United States,4 to reduce the incidence of this serious adverse effect in children.