Smokers looking to quit might benefit from a new study showing that a combination of the smoking cessation medication, varenicline, and nicotine patches is more effective than just varenicline alone.

Varenicline is marketed by Pfizer and is a prescription drug that’s used to treat addiction by stimulating nicotine receptors more weakly than nicotine does. It is used to reduce cravings and also the pleasant “buzz” feeling after smoking tobacco, which can help wean some patients off cigarettes.

In the study published in JAMA, researchers from Stellenbosch University, Cape Town, South Africa assigned 446 smokers either to nicotine patches or placebo ones two weeks before a target quit date in order to test whether the patches would have an effect in combination with varenicline. The participants, who were also taking varenicline, had 12 weeks to stop smoking. The study authors found that people who received both nicotine replacement therapy (NRT) in the form of a patch, in addition to varenicline, were more likely to quit smoking within 12 weeks; 55.4 percent of those using the combination succeeded, while only 40.9 percent of the others did.

“In this study, to our knowledge the largest study to date examining the efficacy and safety of supplementing varenicline treatment with NRT, we have found the combination treatment to be associated with a statistically significant and clinically important higher continuous abstinence rate at 12 and 24 weeks, as well as a higher point prevalence abstinence rate at 6 months,” the authors wrote.

When it comes to smoking cessation, however, no way is totally easy. People who were on the combination therapy still experienced adverse side effects and reactions, such as nausea, sleep deprivation, skin reactions, constipation, and depression. Those who took only varenicline reported strange dreams and migraines. Before the combination therapy can be approved for clinical use, however, more studies will need to be done to ensure its safety and efficacy.