Mental Health Minister Helen Morton has admitted the State Government is chasing its tail trying to keep ahead of backyard chemists who tweak formulas of synthetic cannabis products to beat bans.
Ms Morton said yesterday the Government would add another 33 chemical compounds to the schedule of banned substances under the Poisons Act within three weeks.
Twenty-two synthetic cannabis substances are already banned.
Chemists seek to get around the ban by slightly altering the chemical formulations of the banned substances.
"It has been difficult to stay in front of the people who dream up these new substances," Ms Morton said. "We have been able to do that with relatively good success in the past couple of years."
But she foreshadowed "precautionary legislation" that would ban any psychoactive substance that did not have a therapeutic use.
Opposition Leader Mark McGowan said the Government had made no progress on the issue since he first raised it two years ago.