CCroydon Divisional Tasking Unit have seized a large amount of 1-4 Butanediol, known as GHB, during a series of warrants in Rowville, Hallam and Seaford this month.
The total amount seized has an estimated street value of more than $550,000.
Forming part of Operations Cronus and Beaches, police attended several properties over the past week and arrested four people.
Police executed warrants at a residential address in Colorado Crescent, Rowville on 15 April, a warehouse in Wedgewood Road, Hallam on 23 April and at a property in Milroy Street, Seaford yesterday.
Police have since charged four people with trafficking a large commercial quantity of GHB.
A 22-year-old man and a 50-year-old man, both from Rowville, were remanded to appear at Melbourne Magistrates' Court on 9 July.
A 30-year-old woman and a 34-year-old man, both from Seaford, were remanded to appear at Melbourne Magistrates' Court today.
