kick a habit

kick a / the habit (to stop doing something habitual; to stop doing something harmful that you have done for a long time; to stop doing something that is a harmful habit, such as smoking, taking drugs etc) — бросить, завязать (о вредной привычке)

Example 1: Of all substances that I have kicked smoking was the hardest.

Example 2: The scheme helps smokers to kick the habit.

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Usually used with smoking or drinking (kick the habit, drug, booze, etc.)

see also
[go cold turkey]
[go on the wagon]
[в завязке]