Medications and Drugs

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Brand Names: Chantix

Generic Name: varenicline (Pronunciation: ver EN e kleen)

• What is varenicline (Chantix)?
• What are the possible side effects of varenicline (Chantix)?
• What is the most important information I should know about varenicline (Chantix)?
• What should I discuss with my health care provider before taking varenicline (Chantix)?
• How should I take varenicline (Chantix)?
• What happens if I miss a dose (Chantix)?
• What happens if I overdose (Chantix)?
• What should I avoid while taking varenicline (Chantix)?
• What other drugs will affect varenicline (Chantix)?
• Where can I get more information?

What is varenicline (Chantix)?

Varenicline is a smoking cessation medicine. It is used together with behavior modification and counseling support to help you stop smoking.

Varenicline may also be used for other purposes not listed in this medication guide.

Chantix 0.5 mg

oblong, white, imprinted with Pfizer, CHX 0.5

Chantix 1 mg

oblong, blue, imprinted with Pfizer, CHX 1.0

What are the possible side effects of varenicline (Chantix)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using this medication and call your doctor at once if you have any mood or behavior changes, or if you feel agitated, hostile, depressed, or have thoughts about suicide or hurting yourself.

Your family or other caregivers should also be alert to changes in your mood or behavior.

Call your doctor at once if you have any of these other serious side effects:

• fever, sore throat, and headache with a severe blistering, peeling, and red skin rash; or
• the first sign of any blistering type of skin rash, no matter how mild.

Less serious side effects may include:

• nausea (may persist for several months);
• stomach pain, indigestion, vomiting, constipation, gas;
• weakness, tired feeling;
• increased appetite;
• unpleasant taste in your mouth;
• headache; or
• sleep problems (insomnia) or unusual dreams.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about varenicline (Chantix)?

Before using varenicline, tell your doctor if you have kidney disease, or a history of mental illness.

Use this medication exactly as it was prescribed for you. Do not use it in larger amounts or for longer than recommended by your doctor. Follow the directions on your prescription label.

Varenicline can cause drowsiness, which may impair your thinking or reactions. You may also have mood or behavior changes when you quit smoking. Until you know how varenicline and the smoking cessation process is going to affect you, be careful if you drive or do anything that requires you to be cautious and alert.

Stop using this medication and call your doctor at once if you have any mood or behavior changes, or if you feel agitated, hostile, depressed, or have thoughts about suicide or hurting yourself.

Your family or other caregivers should also be alert to changes in your mood or behavior.

Less serious side effects are more likely, and you may have none at all. Varenicline can cause persistent nausea for up to several months. Talk to your doctor about any side effect that seems unusual or is especially bothersome.

If you miss a dose, use the medication as soon as you remember. If it is almost time for the next dose, skip the missed dose and wait until your next regularly scheduled dose. Do not use extra medicine to make up the missed dose.

There may be other drugs that can interact with varenicline. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.