Unplanned admissions to two Sydney public hospitals after naltrexone implants

To the Editor: A recent article by Lintzeris and colleagues,1 ostensibly about naltrexone implants, actually has little to do with implant treatment. Only one of the 12 reported cases involved problems linked specifically to naltrexone (antagonist) treatment being administered in implanted rather than oral form. This case involved infection at the implant site — undesirable, certainly, but about as noteworthy as the occasional infections that occur after abdominal surgery or breast implantation, despite antibiotic prophylaxis and careful technique. The remaining 11 admissions reflected not implant use but either the procedure of rapid antagonist induction (RAI) or the desired pharmacological effects for which naltrexone was prescribed in the first place (and one admission for unrelated pneumonia).