Smoking is harmful to health. Medications are often needed to assist in quitting for people with severe tobacco dependence. Varenicline is one of the three most common medications used to quit smoking. It usually needs to be taken for 12 weeks and is effective in relieving nicotine cravings and withdrawal symptoms. Many studies have demonstrated the effectiveness of varenicline for smoking cessation. A comprehensive report based on several papers found varenicline to be more effective in smoking cessation compared to placebo. There was also a meta-analysis of the literature on non-blinded randomized controlled trials that found more patients quit smoking at 24 weeks in the varenicline group compared to the nicotine patch group. This means that varenicline is more effective in quitting symptoms compared to other smoking cessation medications such as nicotine patches.