varenicline (Chantix)

What is varenicline (Chantix)? What is Chantix used for?

Varenicline is an oral drug that is used to promote cessation of smoking. It competes with nicotine from cigarettes for binding to nicotine receptors in the brain. Although varenicline stimulates nicotine receptors like nicotine, it blocks the stronger stimulation by nicotine. Therefore, smokers do not experience the full effect of smoking while taking varenicline. The FDA approved varenicline in May 2006.

What brand names are available for varenicline (Chantix)?


Is varenicline (Chantix) available as a generic drug?


Do I need a prescription for varenicline, Chantix?


What are the side effects of varenicline (Chantix)?

The most common adverse effects of varenicline are:

Headaches, abnormal dreams and taste disturbance also are frequent side effects of varenicline. Varenicline is not addictive and is not a controlled substance; however, some patients may experience irritability and sleep disturbance if varenicline is abruptly discontinued. Varenicline may worsen symptoms of underlying heart disease. Patients may experience psychiatric symptoms such as behavioral changes, agitation, depressed mood, and suicidal behavior during varenicline treatment. Patients should stop taking varenicline if psychiatric symptoms occur. Rare life threatening skin reactions and hypersensitivity reactions have been reported.


What is the average weight gain for those who quit smoking? See Answer

What is the dosage for varenicline (Chantix)?

The recommended dose is 0.5 mg daily for 3 days followed by 0.5 mg twice daily for 4 days, then 1 mg twice daily for the remainder of the treatment period. Duration of therapy is 12 weeks. If treatment is successful, an additional 12 weeks is recommended to increase the chance of long-term abstinence. Those who do not respond or return to smoking after treatment should be encouraged to try again.

Which drugs or supplements interact with varenicline (Chantix)?

Administering varenicline with the nicotine patch may lead to additional adverse effects.

Is varenicline (Chantix) safe to take if I'm pregnant or breastfeeding?

There are no adequate studies in pregnant women.

It is not known whether varenicline is excreted in breast milk. Nursing mothers should consider discontinuing varenicline or breastfeeding because of the potential for adverse effects in the infant.

What else should I know about varenicline (Chantix)?

What preparations of varenicline (Chantix) are available?

Capsules: 0.5 and 0.1 mg

How should I keep varenicline (Chantix) stored?

Varenicline should be stored at room temperature, 15 C to 30 C (59 F to 86 F).


Varenicline (Chantix) is a drug used to assist in smoking cessation. Common side effects of Chantix include constipation, gas, nausea, vomiting, and sleep disturbance.

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