Varenicline (Chantix) is a smoking-cessation medication that helps people quit by

• A. blocking dopamine receptors to eliminate pleasure from smoking.
• B. binding nicotinic receptors as a partial agonist to reduce cravings and block nicotine effects.
• C. increasing nicotine metabolism so urges are shorter.
• D. causing nausea only when a person attempts to smoke while taking it.

Answer: (B)