"Addiction is by definition a chronic relapsing condition. So we shouldn't be shocked by that ... motivation is fickle and can change from day to day.
"[The centre] is a precious resource. There's a budget and they've got a waiting list," he said. It was best if patients received counselling before being admitted. "It's good to get some groundwork in place and strategies for when they encounter high risk situations. If they're going back to the same place they were in before they were admitted, they're probably going to relapse again."
Jodie Harris, of Tryphina House, Whangarei Women's Refuge, said there was not enough resourcing in the region to cope with the "intensive interventions" required for the growing number of addicts presenting to services such as the refuge.
"The addiction will often impact on the individual's ability to keep themselves, their families and the people around them safe. There is a huge social cost to the women, children and families of addicts in our community.
"We firmly believe that the social impact of addictions - welfare, health, justice - in Northland is too high to not fully resource the services required."
Timatanga Hou's clinical nurse manager, Rachel Beech, said people were admitted to the centre for two to three weeks, compared with hospital ward detoxes which were usually completed in three to five days.
Half the patients she had were going on to another residential treatment programme.
People's perceptions of what a patient in detox looked like were "quite wrong", she said.
"We have a pre-admission screen. There are clear rules around behaviour and it's not a significant problem. People choose to come here. They're in the process and thinking about what needs to be accomplished here ... there is no violence tolerated."