On the Kronic Facebook page, which has more than 8,500 followers, some users said the law change would mean they would return to using cannabis.
"So what now?" Johnny asked. "Start smoking illegal stuff again? This helped me quit weed."
Graeme said he had enjoyed "a few months of not haveing (sic) to watch for the law" when he smoked Kronic, and now the law change will push users towards Class B drugs and alcohol, and will make criminals out of many users.
Others are worried about the risks of buying cannabis from tinny houses and gangs who may be cutting the drug with other substances.
Michael was concerned about the health risks of smoking synthetic cannabis, but was "sure it's better than the fly sprayed smoke that the dealers up the road sell. And [you have got to] hope you don't get bashed for going there as well".
Many users pointed out that alcohol and cigarettes have been proven to harm users yet remain legal.
"This just makes me angry for the simple fact is there is a lot harder stuff [people] could be using that are more dangerous and the fact alcohol is not against the law and it causes more death, violence and abuse than anything else," Mandy said.
Allun said it was hypocritical of Prime Minister John Key to say it was unacceptable synthetic cannabis is freely available to young people, while alcohol, cigarettes and even fast food pose health risks.
"Good job putting the illegal dealers back on the vendor list for everyone that now cannot get a legal substitute," he said.
As it will remain legal to possess and use the products, users are planning to stockpile on the products.
Kronic's online store has began discounting the price of their range in order to get rid of the stock before the ban comes into effect.
Users have created two Facebook pages, Keep Kronic in our Shops!! and Keep Kronic/synthetic Marijuana products legal!, both with around 70 members, and plans are forming for protests against the ban in Auckland, Hamilton, Wellington, Christchurch and other centres this Friday.
- HERALD ONLINE