Nevirapine induced opiate withdrawal among injection drug users with HIV infection receiving methadone.
BACKGROUND
Pharmacokinetic interactions complicate and potentially compromise the use of antiretroviral and other HIV therapeutic agents in patients with HIV disease. This may be particularly so among those receiving treatment for substance abuse.


OBJECTIVE
We describe seven cases of opiate withdrawal among patients receiving chronic methadone maintenance therapy following initiation of therapy with the non-nucleoside reverse transcriptase inhibitor, nevirapine.


METHODS
Retrospective chart review.


RESULTS
In all seven patients, due to the lack of prior information regarding a significant pharmacokinetic interaction between these agents, the possibility of opiate withdrawal was not anticipated. Three patients, for whom methadone levels were available at the time of development of opiate withdrawal symptoms, had subtherapeutic methadone levels. In each case, a marked escalation in methadone dose was required to counteract the development of withdrawal symptoms and allow continuation of antiretroviral therapy. Three patients continued nevirapine with methadone administered at an increased dose; however, four chose to discontinue nevirapine.


CONCLUSIONS
To maximize HIV therapeutic benefit among opiate users, information is needed about pharmacokinetic interactions between antiretrovirals and therapies for substance abuse.
Altice
F L
FL
Yale University AIDS Program, New Haven, Connecticut 06510-2283, USA.
Friedland
G H
GH
Cooney
E L
EL
D000328:Adult; D019380:Anti-HIV Agents / Q000009:adverse effects*; D004347:Drug Interactions; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008691:Methadone / Q000627:therapeutic use; D008875:Middle Aged; D009294:Narcotics / Q000627:therapeutic use; D019829:Nevirapine / Q000009:adverse effects*; D009293:Opioid-Related Disorders / Q000150:complications* / Q000534:rehabilitation; D012189:Retrospective Studies; D015819:Substance Abuse, Intravenous / Q000150:complications* / Q000534:rehabilitation; D013375:Substance Withdrawal Syndrome / Q000209:etiology*
D019380:Anti-HIV Agents; D009294:Narcotics; D019829:Nevirapine; D008691:Methadone