His father said he was unaware Michael had been dabbling in recreational drug use.
"I've had a couple of shocks over the past week. I thought Michael had been going to uni - but he hasn't."
Murray said he and the rest of the family were still trying to come to grips with the events leading up to Michael's admission.
"I have never seen so many young boys crying. It's been a hell of a shock. I didn't even know this stuff existed before last week," Murray said.
"The other thing I'm quite shocked about is just how prolific the use of cannabis as well as all this synthetic stuff is. I'm also concerned about how many young people know where to get it and how cheap it is."
Murray said it was difficult to give other parents advice on how to avoid this happening.
"Being a parent - it's all about trust. I guess, it's probably watching the peer group. But sometimes it's the people you least expect."
NBOMe is sold as a white powder or in capsules. Recreational doses are measured in tiny microgram quantities - less than the size of a match-head - so it is very easy to use too much.
Hallucinations, confusion and agitation are common symptoms, sometimes leading to uncontrollable violent behaviour. Use of the drug has been associated with deaths in Australia and Asia.
Police and health officials are warning people to avoid any drug that is sold as an NBOMe or an 'LSD-type drug' and seek medical help immediately for anyone suffering from adverse reactions.
Detective Senior Sergeant Jason Stewart said the last time there was a cluster of people requiring treatment after using synthetic drugs in Christchurch was around six months ago.
Police were working closely with Customs and other agencies nationwide to target users and distributors of these substances, as the effects of these drugs could be unpredictable and highly dangerous.
Investigations into the drug incidents were ongoing and police were keen to hear from anyone with any information that may assist.
• If you see anything suspicious or have any information on drug dealing in your community contact your local police station or, in an emergency, call 111.
• Information can also be provided anonymously by calling Crimestoppers on 0800 555 111.