Different doses, durations and modes of delivery of nicotine replacement therapy for smoking cessation
There is high-certainty evidence that using combination nicotine replacement therapy (NRT) (fast acting form + patch) rather than a single form of NRT increases the chances of successfully quitting smoking, whether that single form is a patch or a fast-acting version (e.g. gum). Higher dose nicotine gum works better than low dose gum (high-certainty evidence) and higher dose nicotine skin patches probably work better than lower dose patches (moderate-certainty evidence). Starting NRT before quit day is probably better than starting it at the same time as giving up smoking.
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