"I'm an intense person and I'll argue strongly issues I think are important. I don't and have not taken any medication of the sort that's insinuated by Labour MP Kris Faafoi. But I also worry about the precedent that's being set where MPs having to answer questions about medications they might or might not be taking."
Smith has been the subject of similar comments in Parliament since he took stress leave in 2004 after being deposed as newly appointed deputy leader of the National Party following Don Brash's election as leader.
"At the time Don Brash rolled Bill English as leader I took a break. I was exhausted," Smith said.
A spokeswoman for Faafoi said he called Smith today, acknowledged his comments fell below the standard he set for himself and had apologised.
"My understanding is that Mr Smith accepted the apology."
Mental Health Foundation chief executive Shaun Robinson said such comments undermined the progress that had been made.
"We hope that this is the last time this happens in Parliament from any member. We're looking to this Government to provide leadership in the area of mental health and make significant changes to improve the mental health and wellbeing of all New Zealanders. We hope to see a renewed commitment from all members to model this leadership in their words and behaviour," he said in a statement.
An inquiry into mental health is currently under way and due to report back in October. It was instigated as part of Labour's 100-day plan following the election after the party said mental health was in crisis.
The exchange
Andrew Little: That's the traditional and expected flowery and flamboyant approach that that member takes to characterising issues, but I simply draw that member's attention yet again to the Supreme Court decision—
Kris Faafoi: That's the medication.
Andrew Little: —in Awatere Huata v Prebble, where that court, the highest court in the land, said that members of Parliament with party obligations are required to meet those party obligations, and that is not an interference in the functioning of Parliament.
Nick Smith: Supplementary?
Winston Peters: Supplementary question?
Speaker: No, before either member goes, Darroch Ball will stand, withdraw, and apologise. Was he the member who made that interjection? [Member shakes his head] Was it the member in front of him?
Member: No.
Speaker: No? Well, one of those members.
Kris Faafoi: I stand, withdraw, and apologise.