The Mental Health Foundation says language used to describe Jami-Lee Ross' distress is damaging to others with their own mental health troubles.
Mental Health Foundation chief executive Shaun Robinson told Morning Report stigmatising comments that have been made by politicians, commentators and on social media were concerning.
"I think most recently they've come through in some of the ... comments that appear on social media around some of the stories. But again, there are politicians, both local body and national, that are using some language that perhaps needs to be thought about more carefully," Mr Robinson said.
"It goes to that fundamental undermining of people and fear of people when they're going through a mental health issue."
Mr Robinson warned those who were using words like 'unbalanced' or accusing Jami-Lee Ross of blaming his actions on his mental health, were stigmatising mental illness.
"That stigma, that nastiness actually spills over to affect other people, it may be your sister, your brother, someone at your work, it may be you at some point in your life, who also finds yourself going through mental and emotional distress and remembers those attitudes.
He said he knew from his own experiences, there's already self-stigma to deal with.
"It is very easy to feel bad about yourself, to feel shamed, to feel weak and you should be able to cope with this, and to have those kinds of attitudes then amplified through others through their words, even if it's not about you, but somebody who's going through something similar to you, it's damaging."
He said that can stop people from speaking out and seeking help.
The foundation had already been contacted by people who were finding the comments disturbing.
He added there needed to be a clear difference between criticising someone's political decisions and someone's health issue.
"We need to be careful we don't jump into the put-down language we often throw at people when they're making decisions we disagree with, like 'crazy' and 'unstable' as a way of undermining their judgement, particularly when it's relating to someone who is clearly going through some very tough times," he said.
This article was first published on Radio NZ.
Where to get help with mental health
Need to talk?: Free call or text 1737 to talk to a trained counsellor, anytime.
Lifeline: 0800 543 354
Suicide Crisis Helpline: 0508 828 865 / 0508 TAUTOKO
Depression Helpline: 0800 111 757
Samaritans: 0800 726 666
Youthline: 0800 376 633 or email email@example.com
Healthline: 0800 611 116