The sale and possession of magic mushrooms was banned by Minister for Health Mary Harney on January 31st following a meeting with Eoin and Mary Hodkinson after the death of their son.
Previously, it was illegal to sell hallucinogenic mushrooms if they were processed, but not in their raw state.
However, on January 31st Ms Harney introduced a regulation under the Misuse of Drugs Act to make it illegal to sell them in any form.
Afterwards Mr and Mrs Hodkinson said: "We believe that without magic mushrooms Colm would be alive today. We hope our campaign will save others."
Following the inquest yesterday, James McDonald, the owner of the Hemp Store in Dublin where Mr Hodkinson is believed to have bought the hallucinogenic mushrooms, said his customers were "always given advice" about how to consume magic mushrooms.
He added that vintners had been involved in lobbying to outlaw the product as it had a detrimental effect on their sales.
Shane O'Connor, owner of the Hemp stores in Dublin, Galway and Waterford which previously sold magic mushrooms, described Mr Hodkinson's death as a tragedy.
However, he said that by banning mushrooms, Ms Harney had pushed them into the black market drugs trade, which was far more detrimental.
He added that Ms Harney had "rushed this legislation through without consultation" with business owners who had sold the product and this was unacceptable.
He said that he, along with others, are considering a legal challenge against this ban.
He added that many people involved in the legal sale of the product had been forced out of business as a result of the ban.
Darcy Petticrew, owner of Himalayan Crafts Ltd in Co Meath which previously sold magic mushrooms, said the ban was a "knee-jerk reaction" to Mr Hodkinson's tragic death.
He said that even though Mr Hodkinson had consumed only a small amount of alcohol and cannabis, they could not be ruled out as factors in his death.
"Magic mushrooms are a product I still think everyone should try once in their life."
Liam Twomey, Fine Gael spokesman on health, said "anything hallucinogenic can be addictive".
Dr Twomey added he had "no sympathy" for people who previously sold this "dangerous" product.