Marketing start-up Iterable dismissed its chief executive over violations of company policy, the company said in a note to employees on Monday.

The fired chief executive, Justin Zhu, said the board’s chief reason for ousting him was that he took LSD, an illegal drug in the US, before a meeting in 2019. Zhu said he was experimenting by taking a limited amount of the drug, or microdosing, in an effort to boost his focus.

In an email to staff, co-founder Andrew Boni said Zhu’s dismissal was over unspecified violations of “Iterable’s Employee Handbook, policies and values”. The board replaced Zhu with Boni as chief executive, the email said. A spokeswoman for the San Francisco-based company didn’t immediately provide a comment.

Zhu’s “behaviour also undermined the board’s confidence in Justin’s ability to lead the company going forward” Boni wrote in his note. He also described Zhu as a “world-class innovator and creative thinker” whose “vision, creativity and passion will remain a core part of our culture”.

Although the use of drugs like LSD remain controversial, they have gained acceptance in parts of Silicon Valley and in some medical circles. Steve Jobs, the late co-founder of Apple, told his biographer: “Taking LSD was a profound experience, one of the most important things in my life.” MDMA, known as ecstasy, is currently at the Food and Drug Administration’s Phase III stage of testing for use to treat post-traumatic stress disorder.

Iterable was founded in 2013 and has grown quickly, attracting customers such as DoorDash and Zillow Group. Its investors include Index Ventures, Charles River Ventures and Viking Global Investors. It is valued at about $2 billion, according to research firm PitchBook.