The Japanese health ministry on Tuesday decided to ban six synthetic cannabinoids with structures similar to HHCH, which was recently designated an illicit drug after gummies containing the compound made a number of people fall ill.

Possession and distribution of the six substances, which include HHCP, or hexahydrocannabiphorol, will be prohibited from Jan. 6.

HHCH, or hexahydrocannabihexol, had not been banned in Japan until earlier this month, although the substance has a structure similar to THC, or tetrahydrocannabinol, which is derived from cannabis and had already been prohibited in the country.

Even after HHCH was regulated, products containing HHCP and other substances have been marketed and caused health issues, prompting the Health, Labor and Welfare Ministry to prohibit last week sales of 38 items such as gummies and cookies that contain the compounds at stores and online.

A ministry panel on Tuesday approved adding the six compounds to the list of controlled substances, prohibiting their manufacture, sale and possession except for medical purposes.

The moves to tighten control on synthetic cannabinoids came amid a series of incidents involving so-called cannabis gummies. On Nov. 4, five individuals, ranging in age from their teens to their 50s, fell ill after consuming gummies in packages labeled HHCH distributed by a man at a festival in western Tokyo.

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