Lisbon 2017 Abstract talk

Exploration of the benefits of methadone treatment for dual users of heroin and crack who inject or have previously injected drugs – preliminary findings

Felicia Heidebrecht, Jenny Corless and Lynne Dawkins


Methadone is used world-wide as a first choice treatment for opioid dependency, and higher doses have been shown to be associated with better treatment outcomes. However, methadone also poses risks, especially at higher doses and in combination with other depressant drugs, the most critical being respiratory overdose. Some individuals continue using drugs while on methadone, and more recent studies suggest this is more common for dual users of heroin and crack. Intravenous (IV) drug use poses additional risks; more frequent injecting and poor technique increase the risk of overdose and physical health complications. Dual users injecting drugs might therefore be at higher risk of health problems when prescribed higher doses of methadone.

Research Question

To explore treatment journeys of IV drug users in methadone treatment by comparing high (≥70 mg daily) vs. low  (<70 mg daily) dose users on health outcomes and crack use.


Setting: Two community drug services in London, UK.
Participants: Current or previous IV heroin users smoking or injecting crack in methadone treatment (n=20, recruitment ongoing).
Measurements: EQ-5D and in-depth interviews based on questionnaires with scale ratings, closed and open questions covering drug use, injecting and treatment history, living situation, physical health.


All participants still injecting drugs at the time of the interview were IV users of crack.

Preliminary findings suggest that overall 80% (86% on high and 77% on low dose) stopped IV drug use at the time of the interview. Compared to low dose more participants on high dose achieved abstinence from heroin (57% vs 8%) and crack (43% vs 8%).

Despite this, compared to low dose, participants on high dose continued IV drug use while on methadone for longer (14 ±-7.4 years vs. 9 ± 6.8 years), were more like to use high-risk injection sites (groin, neck) (71% vs 38%) and they were more likely to continue injecting until completely exhausting the veins at high-risk sites: their most frequent reason for stopping IV use was due to difficulty finding veins on a high-risk site, or a related severe health complication, whereas many participants on low dose injected only on lower risk sites and switched to smoking when not able to find veins. Furthermore, more participants on high dose reported numerous overdoses (43% vs. 14%), hepatitis infection (70% vs. 50%), rated their health lower on EQ-5D, and experienced more severe cardiovascular problems.


These preliminary results suggest that the benefits of high doses of methadone on achieving abstinence from heroin might come at the cost of poorer physical health in dual users of heroin and crack with a history of IV drug use. The route of administration of crack might be an indicator of treatment outcomes. The data collection is ongoing and statistical analyses as well as qualitative analysis of open answers are planned on the full data set.