In 1995, the then National Drugs and Poisons Scheduling Committee (NDPSC) found that new toxicological data for methazole had revealed dose-related increases in the incidence of cataracts in the offspring of rat dams dosed with methazole. In response to this new information, the NDPSC rescheduled methazole from Schedule 6 to Schedule 7 of the Standard for the Uniform Scheduling of Drugs and Poisons (now the Standard for the Uniform Scheduling of Medicines and Poisons). Schedule 7 compounds are categorised as toxic and must have the signal heading ‘Dangerous Poison’ on the label.
The primary registrant, Sandoz, voluntarily withdrew its products containing methazole and ceased marketing them in 1993. Sandoz did not renew its methazole product registrations, and the remaining amount of stock in the marketplace was considered to be negligible by 1996.
In July 1995, prompted by the NDPSC’s regulatory decision, the APVMA began a special review of methazole based on the toxicological concerns and to consolidate the earlier regulatory action.