The Scottish ministers code of conduct has been revised following the resignation of Mark McDonald over alleged sexual misconduct.
The Aberdeen Donside MSP quit his post as early years and childcare minister after the claims surfaced late last year.
The Press and Journal later revealed that he had sent a text message to a woman which made reference to a sex act.
The woman said she complained about Mr McDonald’s behaviour because “people have to change”.
A new edition of the code of conduct has now been published and includes a specific prohibition on “harrassing, bullying or other inappropriate behaviour” by ministers for the first time.
It also instructs ministers to treat civil servants with “consideration and respect”.
It states: “Ministers should be professionals in all their dealings and treat all those with whom they come into contact with consideration and respect.
“Working relationships, including with civil servants, ministerial and parliamentary colleagues and parliamentary staff should be proper and appropriate.
“Harassing, bullying or other inappropriate or discriminating behaviour, wherever it takes place, is not consistent with the Ministerial Code and will not be tolerated.”
First Minister Nicola Sturgeon initially backed the city MSP to remain at Holyrood but the 37-year-old was subsequently suspended from the SNP and the parliamentary group when it emerged a second woman had complained about his conduct.
Ms Sturgeon previously said she did not want to put an “artifical timescale” on the inquiry, which was launched on November 16.
“When specific allegations are made about specific individuals, it’s important due process and, while an investigation is ongoing, appropriate confidentiality, is respected,” she said in a BBC radio interview.
“I don’t think – and I believe this point very, very strongly – I don’t think we will encourage women to come forward and raise issues like this if women then think there’s going to be a running commentary as investigations are undertaken.”
Mr McDonald has not attended any Holyrood debates since his suspension, and the former Aberdeen councillor is listed as an “independent” on the Scottish Parliament website.