varenicline
Varenicline (Chantix) is a medication that's used to help you quit smoking. The dosage is based on a timeline, so make sure to follow the directions carefully. Varenicline (Chantix) doesn't contain nicotine like some other medications that help you quit smoking, but it can cause side effects, including nausea and trouble sleeping. In 2021, the manufacturer Pfizer recalled and stopped making the brand-name version (called Chantix) because of potentially cancer-causing chemicals found in the medication during production. There are still generic versions available because the benefits of this medication are thought to be greater than the potential risks.
What is Varenicline (Chantix)?
What is Varenicline (Chantix) used for?
- Smoking cessation (quitting smoking)
How Varenicline (Chantix) works
Varenicline (Chantix) is a partial nicotine receptor agonist. It works in the same part of your brain as nicotine. This helps lower cravings and prevent withdrawal symptoms.
Drug facts
Side effects of Varenicline (Chantix)
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Common Side Effects
- Nausea (30%)
- Trouble sleeping (18%)
- Headache (15%)
- Unusual, vivid, or strange dreams (13%)
- Constipation (8%)
- Tiredness (7%)
- Stomach pain (7%)
- Gas (6%)
- Dry mouth (6%)
- Vomiting (5%)
- Indigestion (5%)
- Change in taste (5%)
Less Common Side Effects
- Drowsiness
- Itching
- Rash
- Trouble breathing
- Cold-like symptoms
- Changes in appetite (larger appetite or loss of appetite)
- Nightmares
- Heartburn
Varenicline (Chantix) serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Severe allergic reaction: swelling of the face or mouth (tongue, lips, and gums); trouble breathing
- Severe skin reaction: skin rash with lesions (sores) or bumps
- Accidental injuries: feeling tired, dizzy, or having trouble focusing before performing tasks (e.g., driving a car)
More on Varenicline (Chantix) side effects
The following Varenicline (Chantix) side effects have also been reported
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Less common
black, tarry stools
bloating or swelling of the face, arms, hands, lower legs, or feet
bloody stools
blurred vision
burning feeling in the chest or stomach
chest pain or discomfort
chills
cold hands and feet
cold sweats
confusion
cool, pale skin cough
deep or fast breathing with dizziness
difficult or labored breathing
dizziness
fainting
fast, pounding, or irregular heartbeat or pulse
flushed, dry skin
fruit-like breath odor
headache
headache, severe and throbbing
increased hunger
increased thirst
increased urination
indigestion
loss of consciousness
nervousness
nightmares
noisy breathing
nosebleed
numbness of the feet, hands and around the mouth
pain or discomfort in the arms, jaw, back, or neck
pale skin
pounding in the ears
rapid weight gain
seizures
shakiness
slow heartbeat
slurred speech
stomach pain or upset
sweating
swollen, painful, or tender lymph glands in the neck, armpit, or groin
tenderness in the stomach area
tightness in the chest
tingling of the hands or feet
troubled breathing with exertion
unexplained weight loss
unusual bleeding or bruising
unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
unusual weight gain or loss
vomiting
vomiting of blood or material that looks like coffee grounds
Rare
Agitation
bleeding gums
blood in the urine or stools
dark urine
decrease in height
decreased awareness or responsiveness
difficulty in swallowing
feeling of fullness
general feeling of illness
hostility
increased sensitivity of the skin to sunlight
increased volume of pale, dilute urine
irritability
itching, skin rash
loss of appetite
mood changes
muscle pain, cramps, or twitching
numbness or tingling in the hands, feet, or lips
pain or burning in the throat
pains in the stomach, side, or abdomen, possibly radiating to the back
pinpoint red spots on the skin
red, scaling, or crusted skin
redness or other discoloration of the skin
severe sleepiness
severe stomach pain
severe sunburn
sores, ulcers, or white spots on the lips, tongue, or inside the mouth
tenderness, pain, swelling, warmth, skin discoloration, and prominent superficial veins over the affected area
uncontrolled eye movements
yellow eyes or skin
Incidence not known
Anger
behavior changes
discouragement
feeling sad or empty
feelings of panic
irregular heartbeat
loss of interest or pleasure
mood swings
restlessness
seeing, hearing, or feeling things that are not there
sleepwalking
thoughts of killing oneself
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Abnormal dreams
absence of menstruation
change in taste
difficulty having a bowel movement
difficulty in moving
excess air or gas in the stomach or bowels
joint pain or swelling
lack or loss of strength
loss of taste
muscle stiffness
passing gas
toothache
trouble sleeping
Less common
Belching
body aches or pain
burning, dry, or itching eyes
continuing ringing or buzzing or other unexplained noise in the ears
decreased interest in sexual intercourse
discharge, excessive tearing
ear congestion
feeling of constant movement of self or surroundings
feeling of warmth
hearing loss
inability to have or keep an erection
increased appetite
increased urge to urinate during the night
loss in sexual ability, desire, drive, or performance
loss of voice
nightmares
redness in the joints
redness of the face, neck, arms and occasionally, upper chest
redness, pain, swelling of the eye, eyelid, or inner lining of the eyelid
sensation of spinning
sleepiness or unusual drowsiness
stomach discomfort
stuffy or runny nose
transient, mild, pleasant aromatic odor
trouble concentrating
waking to urinate at night
Rare
Change in color vision
difficulty seeing at night
increased sensitivity of the eyes to sunlight
night blindness
seeing floating dark spots or material before the eyes
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Get your GoodRx coupon
Pros and cons of Varenicline (Chantix)
Pros
- Generic version is a safe option that works just as well as the brand-name version did.
- Helps to control cravings and lessen withdrawal symptoms
- Can quit smoking gradually while taking the medication
- Safe to use if you have liver problems
Cons
- Can cause nausea
- Can make your dreams vivid or unusual
- Can cause you to feel the effects of alcohol more intensely
- Need to take for 3 months (or even longer for some people)
Pharmacist tips for Varenicline (Chantix)
- Set a quit date with your healthcare provider and then start varenicline (Chantix) 1 week before that date. If you don't have a quit date, you can still start using varenicline (Chantix) and plan to quit either within the first month or gradually over 12 weeks.
- Take varenicline (Chantix) with food and a full glass of water to help lessen nausea. Nausea is a common side effect of the medication; it's typically mild, but it can be more bothersome for some people. If nausea gets too bothersome or doesn't go away, talk to your provider to see if they can change your dose.
- Limit how much alcohol you drink, as varenicline (Chantix) can make the effects of alcohol more intense.
- Because varenicline (Chantix) doesn't contain nicotine, you shouldn't experience as intense of withdrawal symptoms when you finish treatment as you would if you stopped smoking "cold turkey." Some people do have mood changes or nightmares while taking this medication. If these side effects are severe or bothersome, talk to your provider about alternatives.
- Quitting smoking can be difficult. Talk to your healthcare provider for extra support on your journey to quit smoking. Even if you slip up and have a cigarette, it doesn't mean that varenicline (Chantix) isn't working.
- Let your healthcare provider know if you're pregnant or plan to become pregnant because varenicline (Chantix) might not be the best option for you.
Common questions about Varenicline (Chantix)
The brand-name Chantix isn't available anymore. But FDA-approved generic versions of varenicline are still available. The pharmaceutical manufacturer discontinued the Chantix brand in the summer of 2021 after it was discovered to have higher-than-normal amounts of nitrosamines (chemical by-products that might raise the risk of cancer when consumed long term). The generic version is made to work just as well as the brand-name version; it just doesn't have a higher-than-acceptable amount of nitrosamines.
When you first start varenicline (Chantix), carefully follow the dosing schedule that your healthcare provider gives you. Take 0.5 mg of varenicline (Chantix) once daily for the first 3 days only, then 0.5 mg twice daily for the next 4 days. After that, you'll take 1 mg of varenicline (Chantix) twice daily. Your treatment should take a total of 12 weeks (unless instructed differently by your healthcare provider). Some people will take varenicline (Chantix) for an extra 12 weeks. Discuss this option with your healthcare provider, especially if you chose to quit smoking gradually over the first 12 weeks of treatment with varenicline (Chantix).
Varenicline (Chantix) starts to lessen your urge to smoke after about a week. You'll need to continue taking this medication in order to get the full benefit.
It's possible to gain weight while taking varenicline (Chantix). But keep in mind that weight gain can also be the result of nicotine withdrawal that your body experiences when you're trying to quit smoking; this can happen with or without varenicline (Chantix) treatment. A recent study showed that people taking varenicline (Chantix) didn't gain a lot of weight after quitting smoking. If you experience weight gain while quitting smoking, talk with your healthcare provider.
There are three different ways to approach quitting smoking when you start varenicline (Chantix). In each approach, you stop smoking at different time points during treatment. One option is to stop smoking 1 week after starting varenicline (Chantix); this is called the fixed quit approach. In the flexible quit approach, you quit smoking within 1 month of starting varenicline (Chantix). Lastly, in the gradual quit approach, you gradually quit smoking within 12 weeks of starting varenicline (Chantix) — you lower the amount of cigarettes you're smoking by 50% during the first 4 weeks, again during the next 4 weeks, keep cutting down during weeks 9 to 12, and then completely stop smoking by the end of 12 weeks or sooner. Discuss with your healthcare provider about your willingness to quit smoking to decide which option best fits your needs.
This might not be the best idea. If you use varenicline (Chantix) with a nicotine patch, you might be more likely to experience side effects like nausea, trouble sleeping, and constipation, especially if you also drink heavily. Your pharmacist or healthcare provider can work with you to come up with a plan to help you quit smoking safely.
There are some people who've experienced mood changes, hallucinations, aggression, anxiety, and psychosis (losing touch with reality) while taking varenicline (Chantix). Over the years, there have been studies showing that there's no difference in the occurrence of these side effects between people who use varenicline (Chantix) and people who didn't use any medication or other smoking cessation medications. But if you or a loved one notices changes in mood or behavior while you're taking varenicline (Chantix), let your healthcare provider know.
How to save using GoodRx
Risks and warnings for Varenicline (Chantix)
Varenicline (Chantix) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Mental health changes and risk of suicide
- Risk factors: History of mental health issues | Drinking alcohol while taking varenicline (Chantix) | People who keep smoking while taking varenicline (Chantix)
Some people have experienced mental health changes while taking varenicline (Chantix). These mental health issues include depression, hallucinations, aggression, anxiety, and even thoughts of suicide. Drinking alcohol while taking varenicline (Chantix) raises your risk of these side effects. You're also more likely to experience them if you had mental health issues (like depression or bipolar disorder) before you started taking varenicline (Chantix). Watch out for any unusual changes in mood, thoughts, or behavior, especially when you first start taking varenicline (Chantix) or when your dose changes. Stop varenicline (Chantix) and tell your healthcare provider right away if you experience any of these changes.
Heart attacks and strokes
- Risk factors: History of heart problems
In rare cases, people taking varenicline (Chantix) have had non-fatal heart attacks or strokes. It isn't clear whether varenicline (Chantix) can raise your risk of these problems happening. If you have heart problems, tell your healthcare provider if you experience any worsening symptoms of your condition while taking this medication. Call 911 or get immediate medical care if you have symptoms of a heart attack (chest discomfort or pain) or stroke (trouble walking, speaking, understanding, or numbness of the face, arms, or legs).
Seizures
- Risk factors: History of seizures | Taking other medications that raise your risk of seizures
Some people have had seizures while they were taking varenicline (Chantix). Seizures can happen in both people who have had and who've never had seizures in the past. Most times, seizures happened within the first month of starting varenicline (Chantix). Let your provider know if you've experienced seizures in the past or take medications to control seizures before starting this medication. Stop varenicline (Chantix) and tell your healthcare provider right away if you think you've had a seizure while taking this medication.
Sleepwalking
Although rare, some people taking varenicline (Chantix) have sleepwalked or performed other actions while sleeping. This can be dangerous and get you hurt, get others hurt, or cause damage to property. If you or your loved ones have noticed sleepwalking, stop taking varenicline (Chantix) and let your healthcare provider know.
Accidental injuries
Some people taking varenicline (Chantix) have reported having traffic accidents and other accidental injuries. Varenicline (Chantix) might cause you to feel drowsy or dizzy and affect your concentration, so make sure you know how the medication affects you before driving or performing activities that require you to be alert.
Allergic reactions
Severe allergic reactions to varenicline (Chantix) are possible, including life-threatening problems like Stevens-Johnson syndrome (SJS) or anaphylaxis (closing of the throat). If you notice painful blisters all over the body, hives, a rash, swelling of the lips or tongue, or difficulty breathing after using varenicline (Chantix), get medical attention or call 911 right away.
More on Varenicline (Chantix) warnings
Varenicline (Chantix) dosage
Typical dosage for Varenicline (Chantix)
Typically, you'll want to start varenicline (Chantix) 1 week before the date you've decided to stop smoking cigarettes or other tobacco products.
- On days 1 to 3: Take 0.5 mg by mouth once daily.
- On days 4 to 7: Take 0.5 mg by mouth twice daily.
- On day 8 and onwards: Take 1 mg by mouth twice daily.
Most people take varenicline (Chantix) for 12 weeks, but sometimes your provider might prescribe an extra 12 weeks.
For people who aren't ready to quit 1 week after starting varenicline (Chantix), talk to your healthcare provider. There are other strategies of when you could stop smoking while taking varenicline (Chantix).
Your dose might differ if you have kidney problems.
More on Varenicline (Chantix) dosage
Interactions between Varenicline (Chantix) and other drugs
More on Varenicline (Chantix) interactions
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
How much does Varenicline (Chantix) cost?
What are alternatives to Varenicline (Chantix)?
News about Varenicline (Chantix)
Varenicline (Chantix) images
