What is opioid substitution treatment?

Opioid substitution treatment is where people who are addicted to opioids (like heroin or morphine) can get a safer medicine instead. This helps reduce withdrawal symptoms and means people can regain stability and improve their health. Here’s what you need to know about opioid substitution treatment.  

What are opioids?   

Opioids can also make people feel relaxed and euphoric. While opioids can be very effective for treating pain, long-term opioid use can lead to physical dependence. Withdrawal symptoms like anxiety and physical discomfort can make it very difficult to stop. For some, this develops into opioid use disorder, where a person continues using opioids even though it’s causing problems in their life
  
Out of all drugs, opioids carry the greatest risk of overdose. A recent Drug Foundation report found that between 2016 and 2023, more than 500 New Zealanders lost their lives to opioid overdose.  

Using opioids sourced from the black market can also put people at risk of taking drugs that aren’t what they expect. We saw this recently with a potent  opioid called nitazenes sold as fake Oxycodone pills.   

How does opioid substitution treatment work?  

Opioid substitution treatment is where people are prescribed medications like methadone or buprenorphine to help manage their opioid withdrawal symptoms, without causing the same high as other opioids.  

In Aotearoa, the Ministry of Health runs the opioid substitution treatment programme. Dr Sam McBride, a Wellington-based psychiatrist and co-chair of the National Association of Opioid Treatment Providers, says:

“OST helps people regain their life, get back into employment, and wide societal benefits - reduced risk of bloodborne viruses, reduced crime, and helping people regain control of their lives."

How do you get opioid substitution treatment in New Zealand? 

The first step in getting opioid substitution treatment is to get a referral from your GP. After this, someone from your local OST service will do an assessment of your drug use history, mental and physical health, and personal goals. This will help them create a tailored treatment plan.  

Once on OST, people often take their medication with support of local pharmacists. Those on methadone usually go to their pharmacy once a day and receive their dose in drink form. In some regions, once a person is stable on OST, they might be allowed to take home doses, reducing the need for regular trips to the pharmacy.   

Dr McBride explains that when people are on the right dose of OST, it helps them do everything they need to in their daily life - driving, caring for their children, and managing responsibilities.  

People have different reasons for taking OST. Not everyone wants to stop using the treatment completely.  “Success is about whether a person can have a good life on OST,” Dr McBride says. While he hopes his clients move away from “harmful drug use,” he says that the goal should be reducing harm.   

What is OST like?  

Andrew Gifford, a Consumer Liaison at the Auckland Opioid Treatment Service, has been on OST for over two decades. Reflecting on his journey, he admits that he initially reluctant to seek treatment but now recognises its tremendous value. “I thought it was a cop-out,” he says, “but it has been life changing. It has given me stability and allowed me to achieve personal goals like graduating.”  

In his role with the Auckland Opioid Treatment Service, Gifford supports people to access and manage opioid substitution treatment. Gifford notes that many people are hesitant about starting OST, often because of misconceptions or stigma. As someone who has his own experience of OST, he believes this helps him connect with clients. “When people see someone who has been through similar experiences, it can build trust and understanding,” he explains. 

What are the downsides of OST? 

While OST can be helpful for many people, it also has some drawbacks. Common side effects include constipation and dry mouth, particularly when starting treatment. Some OST clients report finding regular pharmacy visits inconvenient.  
  
According to both Gifford and Dr McBride, the single biggest barrier that OST clients face is stigma. This can show up as people on OST still being judged as “addicted” because of the belief they’ve swapped one drug for another.  

Gifford recommends that those on OST carry a card to help address misunderstandings (see card below).   

What is the future of OST in New Zealand?   

Dr McBride describes New Zealand’s OST programme as widely available and well-regarded but says there’s room for improvement. He calls for more resources and public funding for a new medication - long-acting injectable buprenorphine.   

This medication has been called a ‘gamechanger’ by patients and doctors. It’s already available in the UK and Australia and means people can get the injection once a month, instead of accessing their medication every day. This means people can have more flexibility, work opportunities, and autonomy.   

If you’re supporting someone on opioid substitution treatment, experts recommend understanding the treatment and its goals, respecting the person’s journey, and supporting their efforts to improve their lives.  

For more information about opioids and OST, see Auckland Opioid Treatment Service or Te Pou If you’re looking at accessing opioid substitution treatment, ask your GP or local alcohol and other drug service. You can also call the Alcohol Drug Helpline (0800 787 797) or visit Health Point to find out what is available in your area.