One of the reasons why it can be difficult to stop smoking is the effects that nicotine has on the chemistry of the brain. Consequently, medications have been developed that can interact with brain cells and help block the effects of nicotine on the brain. One such medication is Chantix, which is a prescription medication used to help people stop smoking.
Varenicline
The active ingredient in Chantix, RxList explains, is varenicline. Varenicline is packaged in the form of a salt with another molecule known as tartrate, which serves to make it crystalize more easily and to make it easier for the compound to dissolve in water. The crystals formed by varenicline are off-white or yellow in color. Chantix comes in two strengths, RxList explains, a 0.5 mg and 1 mg dose pill. In actuality, the 0.5 mg tablet contains 0.85mg of the varenicline tartrate salt, which is the equivalent of 0.5 mg of pure varenicline. Similarly, the 1 mg tablet contains 1.71 mg of varenicline tartrate salt.
Mechanism
Chantix is prescribed to help patients quit smoking. Varenicline works by blocking the pleasurable chemical signals in the brain that are generated by smoking, Drugs.com explains; as a result, by inhibiting the pleasure that smoking can cause, varenicline can reduce a smokers motivation to have a cigarette. Varenicline is a medication which is known as a partial agonist for the α4β2 nicotinic acetylcholine receptor subtype, RxList explains. This nicotinic acetylcholine receptor is a protein found in the brain which generates chemicals that generate a sensation of pleasure in response to nicotine. Varenicline is a partial agonist for this receptor which means that it is able to bind to the receptor. Instead of triggering the release of pleasurable chemicals, however, varenicline is able to block off the receptor. As a result, nicotine consumption does not cause any pleasure sensations, which makes smoking less enjoyable.
Inactive Compounds
Chantix also contains a number of other compounds which have no medical or clinical effects. Chantix tablets also contain microcrystalline cellulose, a protein involved in surrounding the varenicline and protecting it until the tablet is ingested. The body cannot digest cellulose, however, so it passes through the digestive tract unchanged. Other compounds found in a tablet of Chantix include anhydrous dibasic calcium phosphate, magnesium stearate and silicon dioxide; these compounds help support and protect the varenicline and may also make it easier for it to dissolve in the stomach. The pills are coated with Opadry Clear dye, RxList explains, as well as with Opadry white or blue coloring to help distinguish between the 0.5 and 1 mg forms.
