Go cold turkey.
Go cold turkey.
Go cold turkey" means to suddenly stop a habit or addiction without gradual decrease, particularly in the context of quitting drugs, smoking, or alcohol. The phrase is believed to stem from the cold, clammy feel of the skin during withdrawal, similar to a turkey’s skin.
He decided to go cold turkey and quit smoking immediately.
He decided to quit smoking immediately without any gradual reduction.
Going cold turkey can be tough, but it's often the fastest way.
Quitting abruptly can be difficult, but it's often the quickest method.
When she gave up caffeine, she went cold turkey and hasn’t had a coffee since.
When she stopped using caffeine, she quit abruptly and hasn’t had coffee since.