This paper presents a preliminary examination of the use of quetiapine (an antipsychotic drug) amongst a broader sample of people who inject drugs.
Quetiapine fumarate is an atypical antipsychotic drug which has become more commonly prescribed in Australia for certain mental health conditions in the last decade. The Therapeutic Goods Association of Australia (TGA) originally approved quetiapine for use in the treatment of schizophrenia in 2000. Subsequent reviews of the drug by the TGA in 2007 and 2009 have resulted in it also being approved for treatment of bipolar disorder. More recently, in 2010, it was approved for use as a second-line treatment (i.e. where other treatments have proven ineffective or inappropriate) for generalised anxiety disorder and major depressive disorder. Potentially serious side effects of quetiapine include QTc interval prolongation (a cardiac effect which can result in sudden death), weight gain and ex-pyramidal symptoms (movement disorders).
Despite a number of case reports from several countries particularly amongst polysubstance users, there has been little examination of quetiapine use amongst broader samples of drug users. In 2010 and 2011, a number of key experts participating in the Illicit Drug Reporting System (IDRS) raised concerns about quetiapine. When speaking more generally about use of anti-psychotic drugs among people who inject drugs (PWID), quetiapine in particular was raised as an emerging substance of recent use. Discussion of an emerging street market for this drug and its use among those without psychotic disorders occurred during interviews with key experts. Key experts expressed concern with the apparent effects of the medication, mostly in relation to antisocial behaviours, with experiences of users seeming “unreasonable”, “agitated” and “oblivious to the world around them”. One key expert reported that clients had been referred for help with “withdrawing” from this medication.
As a result of these reports, specific questions about licit and illicit quetiapine use were included in the 2011 IDRS survey. In this Bulletin we present a preliminary examination of quetiapine use amongst a broader sample of PWID through analysis of findings from the 2011 IDRS, with a specific focus on Victoria, which had the highest prevalence of use in Australia.
- Quetiapine use and associated problems have been documented overseas
- Lifetime quetiapine use was reported by 41% of the 2011 IDRS sample, and recent use was reported by 22% of the sample
- Recent mental health issues and recent benzodiazepine use were prevalent among those using both licit and illicit quetiapine
- Ice use was frequently reported by those reporting illicit quetiapine use
- Quetiapine use among PWID warrants further research and monitoring