Untreated ADHD leading to addiction and drug harm

A new report shows New Zealand’s failure to adequately diagnose and treat ADHD is likely leading to significant drug harm, including from alcohol and nicotine. 

Neurodivergence and Substance Use, released by the NZ Drug Foundation Te Puna Whakaiti Pāmamae Kai Whakapiri to coincide with ADHD awareness month, pulls together the latest international evidence on how ADHD and autism spectrum disorder (ASD) affect people’s drug use and likelihood of suffering substance use disorders (SUDs). 

The report shows that people with ADHD are significantly more likely to use drugs and to develop SUDs, with one study suggesting as many as 50% of adults with ADHD will meet the criteria for SUD at some point in their lifetime. Evidence also shows that people with ADHD and SUD are more likely to die early, especially if their ADHD is untreated or unmanaged. 

Drug Foundation Executive Director Sarah Helm says that making ADHD diagnosis and treatment more accessible would avoid significant amounts of harm and save the health system money. 

“ADHD is under-diagnosed and under-treated in Aotearoa,” she says. “The people we spoke to for this report confirmed the very real barriers they faced when trying to access diagnosis and support.”  

“It would be so much more humane and cheaper to allow people access to ADHD diagnosis and treatment, preventing not only the costs of addiction, but also other health issues such as organ damage and cancers.” 

Helm says that the evidence linking ADHD and substance harm is stark. One study of people who regularly used illicit stimulants found that 45% screened positive for adult ADHD, and another showed that as many as one in five people with SUD have ADHD.  

“This suggests that a different approach to ADHD diagnosis and support could make a significant contribution to reducing addiction and substance harm," she says. 

The report shows that youth with ADHD who received appropriate and timely pharmacotherapy had an 85% reduction in risk for developing a SUD compared to those not receiving treatment. 

ADHD New Zealand spokesperson Darrin Bull says that the report highlights how barriers to ADHD treatment can seriously affect people’s lives. 

“Untreated ADHD can impact people’s relationships, their employment, and their mental health,” he says. “Add in a heightened risk of drug harm to that mix and you can see why we need to get serious about making support and treatment more accessible.” 

One study suggests that 0.6% of New Zealand adults receive pharmacological treatment for ADHD, yet ADHD prevalence in adults could be as high as 2-6%.  

“The system is failing people with ADHD, and it’s failing them again if they develop an addiction or problematic drug use as a result of their untreated condition,” says Helm. 

“We’ve heard loud and clear from the community that they experience barriers and feelings of mistrust from health services, and this is compounded if they disclose substance use issues – even if their ADHD may be an underlying cause,” she says. 

Alongside a literature summary, the report pulls together themes of community experiences based on interviews of people with lived experience of ADHD and/or ASD and substance use.  

“There is still discrimination and stigmatisation of people who use drugs in our health system that means people are labelled ‘drug seekers’ and denied care,” says Helm.

“This report shows we need to change our approach and create tailored screening and treatments for people with substance use disorder or who have suffered drug harm.” 

The report shows that there is a limited understanding of the relationship between ASD and substance use, and that diagnoses of SUD for this group can be challenging. However, some studies suggest that people with ASD may be at increased risk of harmful use and may be more likely to engage in problematic drinking.  

Report recommendations: 

1. Streamline screening of ADHD in individuals with SUD or substance harm 
2. Increase access to ADHD diagnosis 
3. Introduce clinical guidelines for screening, diagnosis and management of ADHD and ASD in adults 
4. Tailor treatment approaches in the alcohol and other drug (AOD) sector for those with neurodivergence 
5. Offer training on neurodivergence and substance use for the addiction workforce 
6. Enhance community-based support 
7. Ensure approaches to neurodiversity and substance use are equitable, culturally safe and work for Māori 
8. Avoid requiring abstinence before providing ADHD pharmacotherapy in clients with SUD 
9. Fund and expand access to lisdexamfetamine 
10. Trial novel approaches to harm reduction such as stimulant substitution therapy 
11. Increase research on neurodivergence and substance use in Aotearoa New Zealand 
12. Tailor existing harm reduction approaches for those with neurodivergence 

Read the report on the Drug Foundation website.