Guidelines which cover the medicinal use of cannabis are set to be reviewed.

Associate Minister of Health Peter Dunne is asking officials to review protocols he put in place last year, following the case of Nelson teenager Alex Renton.

He said it's a new policy area, so there'll inevitably be fine-tuning as the process develops.

"This is really just saying 'look, given the prominence of the issue, are the guidelines we're following as good as they can be?' and I think they're not too bad but there might be room for improvement."

Mr Dunne is adamant the action is not a response to public pressure, nor lobbying from high profile unionist Helen Kelly...who's fighting terminal cancer.

"The Kelly case hasn't come my way because it's been withdrawn by her oncologist, so that hasn't been a factor in all of this."

Former Trade Union leader Helen Kelly said she gave up her battle to get medicinal cannabis legally, because of all the hoops she had to jump through.

Ms Kelly, who's dying of lung cancer, now buys her cannabis on the black market.

She said it doesn't make sense in a civilised society, where it's easy to get legal medicinal cannabis in other countries.

"It's infuriating, it's ridiculous...every time I think about it I think about all the other people that are ringing me, that are asking what they could do to get hold of some..thinking about their elderly parents..it's crazy."

Associate Health Minister Peter Dunne has today asked his officials to review the guidelines for applying for medicinal cannabis.