December 14, 2007
Interferon therapy for chronic infection with hepatitis B or C virus produces clinical depression in up to one-half of patients treated, the authors wrote. In former injection drug users, the adverse effects of interferon may lead to relapse, potentially reducing the likelihood of achieving sustained virologic response. Guidelines for interferon use, therefore, stress the benefits of screening all patients for depression, anxiety, and substance abuse disorders prior to treatment initiation. In the current research letter, the authors reported "an additional and previously undocumented risk during interferon treatment: initiation of crystal methamphetamine abuse."
The patient, a male, 48, with previously diagnosed depression, began interferon therapy for hepatitis C in June 2003. He completed a full course of interferon and achieved a sustained virologic response. He reported using methamphetamine for the first time while receiving interferon. "That just got me out of my depression, got me out of feeling sick from the interferon, made me feel good," the authors quoted the patient as saying.
However, the patient progressed to "daily problematic use" of methamphetamine within weeks. And although he had previously tested negative for HIV, "his first result following initial use of methamphetamine was reactive," the authors wrote.
"Patients experiencing interferon-induced depression may find the acute methamphetamine-induced increases in monoamines (especially dopamine) alluring," wrote the authors. They noted that in the United States, Canada, and Australia, occasional methamphetamine use by men who have sex with men ranges from 6-40 percent. Among MSM with HIV or a history of substance abuse, prevalence of methamphetamine use is even greater.
"When administering interferon therapy to [MSM] and members of similarly vulnerable communities with a high prevalence of methamphetamine use, clinicians should counsel patients about methamphetamine use and routinely evaluate them for pretreatment antidepressant therapy," the authors concluded.