A fast disintegrating dosage form of varenicline comprising an effective amount of varenicline or a pharmaceutically acceptable salt thereof and at least one pharmaceutically acceptable excipient, wherein the dosage form disintegrates in a patient's oral cavity in less than three minutes. Also provided are a method for reducing nicotine addiction, aiding in the cessation of, or lessening of tobacco use in a subject by administering to the subject an effective amount of the fast disintegrating dosage form of varenicline or pharmaceutically acceptable salts thereof; a method of treating a disorder or condition by administering an effective amount of the fast disintegrating dosage form of varenicline; and, various methods of manufacturing or forming an immediate dosage form of varenicline.