A woman badly injured in a car crash is battling ACC to cover detox treatment after being told she can't have surgery until she comes off her medication.

Helen Watson feels a prisoner in her own home and a slave to her daily routine that involves sorting through the 23 pills she has to take for pain, to help her sleep and stabilise her mood.

All have been prescribed since the crash, nearly two years ago.

"Hence why I've got to go to detox, to slowly wean off these pills, especially the lorazepam and diazepam, because I could end up having seizures and vomiting because I've been on them a long time," she says.

"My doctor said my body's dependent."

The Feilding 41-year-old says before the crash on November 15, 2020 - where she T-boned another car she says didn't have its lights on at an intersection early in the morning - she played sport, worked and lived a normal life.

That's changed.

"I sleep in until maybe about midday. I wake up and take my pills in the morning then I just go back to bed.

"I maybe knit, watch TV, just fall asleep. Sometimes I walk to the dairy, but that's slow. I'm always tired."

When she can she paints too, but the pills' side effects leave her unable to do much.

She has help looking after her home and section, isn't allowed to drive, and often doesn't feel like eating. Since her crash she's lost about 10 kilograms and now weighs under 60kg.

The drugs are also affecting her oral health - her mouth is always dry and she needs regular appointments at a dental hygienist.

Her father died about seven years ago, but Watson often travels to spend time with friends, who make sure she's eating.

One of the injuries she suffered in the crash is a damaged spinal disc, when an airbag exploded under her chin.

Initially, ACC didn't cover the claim, arguing she had existing conditions or injuries, but this was overturned by a review in February.

"Although surgery funding is not an issue directly before me in this review, I note that now that Ms Watson has cover for her cervical disc prolapse, she is entitled to funding for the surgery requested by [Rodney] Gordon, to treat that covered injury," reviewer Ngaire Coddington said.

However, in the 15 months between her crash and Coddington's decision, Watson's medications increased

Gordon, her specialist, who has since retired, told her no one would operate until the amount of medication she's taking was considerably reduced.

Helen Watson takes 23 pills a day for pain relief, to help her sleep, and to control her mood. Photo: Jimmy Ellingham.

That requires weeks at a live-in facility where the medication reduction can be managed - Watson has found a suitable one in Auckland - although ACC isn't yet willing to pay for it.

Watson's advocate Kym Koloni can't understand the decision.

"They have to accept liability for the impact of that accident from the date of that accident.

"On the date of that accident she was not on medication," Koloni says.

"They are trying to find a reason to find a reason to deny her."

Kym Koloni says it's particularly objectionable that ACC raised a sensitive claim from two decades ago, when it's not relevant.

In a statement, ACC's acting deputy chief executive for service delivery Phil Riley says the sensitive claim has no relevance to its assessment of Watson's detox request, but Koloni says the corporation raised it in correspondence about the claim.

Riley says Watson is being asked to complete psychological and psychiatric assessments to see whether detox is the most appropriate treatment.

"We understand Ms Watson has a complex dependency on prescribed medications, which may have been impacted by the effects of her injuries sustained in the car accident."

When RNZ asked for clarification, given Watson wasn't taking medication at the time of her crash, Riley says there's no intent to imply she had a prior drug dependency.

Helen Watson likes to paint when she has the energy. Photo: Jimmy Ellingham.

"The most important consideration for funding a residential detox programme is that it is the most appropriate treatment based on the client's holistic needs."

He says the psychiatrist and psychologist are "best qualified to recommend a safe and lasting medication reduction plan for Ms Watson".

Koloni is seeking an urgent review of ACC's decision, seeking immediate approval for funding Watson's detox.

Meanwhile, Watson continues to struggle as she waits for surgery and lives a drugged-up existence.

"It's hard because I live on my own and I don't really have many friends around me. They're all out of town," she said.

"I'm hanging in there, but it's hard."

Watson says she's grateful for Koloni's support and that of City Doctors in Palmerston North, which helps her with her medication.

Even if detox were approved tomorrow she still faces a wait for a spot at the Auckland clinic. The earliest one available is next year.

-RNZ/Jimmy Ellingham.