Topically applied testosterone gels are a widely used mode of testosterone replacement therapy. A concern associated with the use of testosterone gel is unintentional transfer to children or women by skin contact with the application site. We present a case of female hyperandrogenism most likely caused by transfer of testosterone gel used by her partner. Additionally, we searched the computerized database PUBMED and the FDA medical reviews for case reports and clinical trials concerning transfer risk. Several case reports and the results of clinical trials indicate that transfer of testosterone from gel-treated males to women and children is possible and clinically relevant. Thus, the potential of testosterone transfer in gel users should be recognized as a possible side effect of this form of testosterone replacement therapy.