Chantix

Name: Chantix

How should this medicine be used?

Varenicline comes as a tablet to take by mouth. It is usually taken once a day at first and then twice a day in the morning and evening. Take varenicline with a full glass of water (8 ounces [240 mL]) after eating. Take varenicline at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take varenicline exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Your doctor will probably start you on a low dose of varenicline and gradually increase your dose over the first week of treatment.

There are 3 ways that you can take varenicline to help you quit smoking.

  • You can set a quit date to stop smoking and start taking varenicline 1 week before that date. You may continue to smoke during this first week of varenicline treatment, but make sure to try to stop smoking on the quit date you have chosen.
  • You may start taking varenicline and then quit smoking between 8 and 35 days after starting treatment with varenicline.
  • If you are not sure you are able or if you do not want to quit smoking suddenly, you can start taking varenicline and stop smoking slowly over 12 weeks of treatment. For weeks 1–4, you should try to smoke only half as many of your normal number of cigarettes each day. For weeks 5–8, you should try to smoke only one quarter of your starting daily number of cigarettes. For weeks 9–12, you should continue to try to smoke fewer cigarettes each day until you are no longer smoking at all. Aim to quit completely by the end of 12 weeks or sooner if you feel ready.

It may take several weeks for you to feel the full benefit of varenicline. You may slip and smoke during your treatment. If this happens, you may still be able to stop smoking. Continue to take varenicline and to try not to smoke.

You will probably take varenicline for 12 weeks. If you have completely stopped smoking at the end of 12 weeks, your doctor may tell you to take varenicline for another 12 weeks. This may help keep you from starting to smoke again.

If you have not stopped smoking at the end of 12 weeks, talk to your doctor. Your doctor can try to help you understand why you were not able to stop smoking and make plans to try to quit again.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with varenicline and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/downloads/Drugs/DrugSafety/ucm088569.pdf) or the manufacturer's website to obtain the Medication Guide.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Patient Handout

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Manufacturer

  • Pfizer Laboratories

Side Effects of Chantix

Serious side effects of Chantix may include:

  • New or worse mental health problems, which have been reported in some patients. 
  • New or worse heart or blood vessel (cardiovascular) problems in people who already have cardiovascular problems. Tell your doctor if you have any changes in symptoms during treatment with Chantix. Get emergency medical help right away if you have any of the following symptoms of a heart attack, including:
    • chest discomfort (uncomfortable pressure, squeezing, fullness or pain) that lasts more than a few minutes, or that goes away and comes back
    • pain or discomfort in one or both arms, back, neck, jaw or stomach
    • shortness of breath, sweating, nausea, vomiting, or feeling lightheaded associated with chest discomfort
  • The most common side effects of Chantix include:
    • nausea
    • sleep problems (trouble sleeping or vivid, unusual, or strange dreams)
    • constipation
    • gas
    • vomiting

Tell your doctor about side effects that bother you or that do not go away.

These are not all the side effects of Chantix. Ask your doctor or pharmacist for more information.

Call your doctor for medical advice about side effects.

Chantix and Lactation

Tell your doctor if you are breastfeeding or planning to breastfeed. It is not known if Chantix is excreted in human breastmilk or if it will harm your nursing baby.

Chantix Dosage

Take Chantix exactly as your doctor prescribes it. Follow the directions on your prescription label carefully. 

The recommended dose of Chantix is 1 mg twice daily following a one week titration (gradual increase). Days 1 to 3, 0.5 mg once daily. Days 4 to 7, 0.5 mg twice daily. Day 8 to end of treatment, 1 mg twice daily.

Patients should be treated with Chantix for 12 weeks. For patients who have successfully stopped smoking at the end of 12 weeks, an additional course of 12 weeks' treatment with Chantix is recommended to further increase the likelihood of long-term abstinence.

Patients who do not succeed in stopping smoking during 12 weeks of initial therapy, or who relapse after treatment, should be encouraged to make another attempt once factors contributing to the failed attempt have been identified and addressed.

Consider a temporary or permanent dose reduction in patients who cannot tolerate the adverse effects of Chantix.

Other Requirements

  • Store Chantix at room temperature, 59 to 86°F (15 to 30°C). 
  • Safely dispose of Chantix that is out of date or no longer needed. 
  • Keep Chantix and all medicines out of the reach of children.

Chantix FDA Warning

WARNING: SERIOUS NEUROPSYCHIATRIC EVENTS

Serious neuropsychiatric events including, but not limited to, depression, suicidal ideation, suicide attempt, and completed suicide have been reported in patients taking Chantix. Some reported cases may have been complicated by the symptoms of nicotine withdrawal in patients who stopped smoking. Depressed mood may be a symptom of nicotine withdrawal. Depression, rarely including suicidal ideation, has been reported in smokers undergoing a smoking cessation attempt without medication. However, some of these symptoms have occurred in patients taking Chantix who continued to smoke.

All patients being treated with Chantix should be observed for neuropsychiatric symptoms including changes in behavior, hostility, agitation, depressed mood, and suicide-related events, including ideation, behavior, and attempted suicide. These symptoms, as well as worsening of pre-existing psychiatric illness and completed suicide, have been reported in some patients attempting to quit smoking while taking Chantix in the postmarketing experience. When symptoms were reported, most were during Chantix treatment, but some were following discontinuation of Chantix therapy.

These events have occurred in patients with and without pre-existing psychiatric disease. Patients with serious psychiatric illness such as schizophrenia, bipolar disorder, and major depressive disorder did not participate in the premarketing studies of Chantix, and the safety and efficacy of Chantix in such patients has not been established.

Advise patients and caregivers that the patient should stop taking Chantix and contact a healthcare provider immediately if agitation, hostility, depressed mood, or changes in behavior or thinking that are not typical for the patient are observed, or if the patient develops suicidal ideation or suicidal behavior. In many postmarketing cases, resolution of symptoms after discontinuation of Chantix was reported, although in some cases the symptoms persisted; therefore, ongoing monitoring and supportive care should be provided until symptoms resolve.

The risks of Chantix should be weighed against the benefits of its use. Chantix has been demonstrated to increase the likelihood of abstinence from smoking for as long as one year compared to treatment with placebo. The health benefits of quitting smoking are immediate and substantial. 

What should i discuss with my health care provider before taking varenicline (chantix)?

To make sure you can safely take varenicline, tell your doctor if you have any of these other conditions:

  • heart disease, circulation problems;
  • kidney disease (or if you are on dialysis); or
  • a history of depression or mental illness.

FDA pregnancy category C. It is not known whether varenicline will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.

It is not known whether varenicline passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

Do not give this medication to anyone under 18 years old

What should i avoid while taking varenicline (chantix)?

This medication 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 are going to affect you, be careful if you drive or do anything that requires you to be cautious and alert.

Do not use other medications to quit smoking while you are taking varenicline, unless your doctor tells you to.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Shortness of breath.
  • Feeling confused.
  • Hallucinations (seeing or hearing things that are not there).
  • Very upset stomach or throwing up.
  • Seizures.
  • A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away, and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.
  • Heart attack and stroke have rarely happened in people taking this medicine. However, smoking may also raise the chance for these events. Call your doctor right away if you have signs of heart attack like chest pain that may spread to the arms, neck, jaw, back, or stomach; sweating that is not normal; or feeling sick or throwing up. Call your doctor right away if you have signs of stroke like change in strength on 1 side is greater than the other; eyesight, speech, or balance problems; change in thinking clearly and with logic; or very bad headache.
  • Sleepwalking has happened with Chantix. Sometimes, this can lead to harm to you or others. Call your doctor right away if you start to sleepwalk.

If OVERDOSE is suspected

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Drug Interactions

Based on varenicline characteristics and clinical experience to date, Chantix has no clinically meaningful pharmacokinetic drug interactions [see Clinical Pharmacology (12.3)].

Use with Other Drugs for Smoking Cessation

Safety and efficacy of Chantix in combination with other smoking cessation therapies have not been studied.

Bupropion

Varenicline (1 mg twice daily) did not alter the steady-state pharmacokinetics of bupropion (150 mg twice daily) in 46 smokers. The safety of the combination of bupropion and varenicline has not been established.

Nicotine replacement therapy (NRT)

Although co-administration of varenicline (1 mg twice daily) and transdermal nicotine (21 mg/day) for up to 12 days did not affect nicotine pharmacokinetics, the incidence of nausea, headache, vomiting, dizziness, dyspepsia, and fatigue was greater for the combination than for NRT alone. In this study, eight of twenty-two (36%) patients treated with the combination of varenicline and NRT prematurely discontinued treatment due to adverse events, compared to 1 of 17 (6%) of patients treated with NRT and placebo.

Effect of Smoking Cessation on Other Drugs

Physiological changes resulting from smoking cessation, with or without treatment with Chantix, may alter the pharmacokinetics or pharmacodynamics of certain drugs (e.g., theophylline, warfarin, insulin) for which dosage adjustment may be necessary.

Drug Abuse and Dependence

Controlled Substance

Varenicline is not a controlled substance.

Dependence

Humans

Fewer than 1 out of 1,000 patients reported euphoria in clinical trials with Chantix. At higher doses (greater than 2 mg), Chantix produced more frequent reports of gastrointestinal disturbances such as nausea and vomiting. There is no evidence of dose-escalation to maintain therapeutic effects in clinical studies, which suggests that tolerance does not develop. Abrupt discontinuation of Chantix was associated with an increase in irritability and sleep disturbances in up to 3% of patients. This suggests that, in some patients, varenicline may produce mild physical dependence which is not associated with addiction.

In a human laboratory abuse liability study, a single oral dose of 1 mg varenicline did not produce any significant positive or negative subjective responses in smokers. In non-smokers, 1 mg varenicline produced an increase in some positive subjective effects, but this was accompanied by an increase in negative adverse effects, especially nausea. A single oral dose of 3 mg varenicline uniformly produced unpleasant subjective responses in both smokers and non-smokers.

Animals

Studies in rodents have shown that varenicline produces behavioral responses similar to those produced by nicotine. In rats trained to discriminate nicotine from saline, varenicline produced full generalization to the nicotine cue. In self-administration studies, the degree to which varenicline substitutes for nicotine is dependent upon the requirement of the task. Rats trained to self-administer nicotine under easy conditions continued to self-administer varenicline to a degree comparable to that of nicotine; however in a more demanding task, rats self-administered varenicline to a lesser extent than nicotine. Varenicline pretreatment also reduced nicotine self-administration.

Chantix - Clinical Pharmacology

Mechanism of Action

Varenicline binds with high affinity and selectivity at α4β2 neuronal nicotinic acetylcholine receptors. The efficacy of Chantix in smoking cessation is believed to be the result of varenicline's activity at α4β2 sub-type of the nicotinic receptor where its binding produces agonist activity, while simultaneously preventing nicotine binding to these receptors.

Electrophysiology studies in vitro and neurochemical studies in vivo have shown that varenicline binds to α4β2 neuronal nicotinic acetylcholine receptors and stimulates receptor-mediated activity, but at a significantly lower level than nicotine. Varenicline blocks the ability of nicotine to activate α4β2 receptors and thus to stimulate the central nervous mesolimbic dopamine system, believed to be the neuronal mechanism underlying reinforcement and reward experienced upon smoking. Varenicline is highly selective and binds more potently to α4β2 receptors than to other common nicotinic receptors (>500-fold α3β4, >3,500-fold α7, >20,000-fold α1βγδ), or to non-nicotinic receptors and transporters (>2,000-fold). Varenicline also binds with moderate affinity (Ki = 350 nM) to the 5-HT3 receptor.

Pharmacokinetics

Absorption

Maximum plasma concentrations of varenicline occur typically within 3–4 hours after oral administration. Following administration of multiple oral doses of varenicline, steady-state conditions were reached within 4 days. Over the recommended dosing range, varenicline exhibits linear pharmacokinetics after single or repeated doses.

In a mass balance study, absorption of varenicline was virtually complete after oral administration and systemic availability was ~90%.

Food Effect

Oral bioavailability of varenicline is unaffected by food or time-of-day dosing.

Distribution

Plasma protein binding of varenicline is low (≤20%) and independent of both age and renal function.

Elimination

The elimination half-life of varenicline is approximately 24 hours.

Metabolism

Varenicline undergoes minimal metabolism, with 92% excreted unchanged in the urine.

Excretion

Renal elimination of varenicline is primarily through glomerular filtration along with active tubular secretion possibly via the organic cation transporter, OCT2.

Specific Populations

There are no clinically meaningful differences in varenicline pharmacokinetics due to age, race, gender, smoking status, or use of concomitant medications, as demonstrated in specific pharmacokinetic studies and in population pharmacokinetic analyses.

Age: Geriatric Patients

A combined single- and multiple-dose pharmacokinetic study demonstrated that the pharmacokinetics of 1 mg varenicline given once daily or twice daily to 16 healthy elderly male and female smokers (aged 65–75 years) for 7 consecutive days was similar to that of younger subjects.

Age: Pediatric Patients

Because the safety and effectiveness of Chantix in pediatric patients have not been established, Chantix is not recommended for use in patients under 18 years of age. Single and multiple-dose pharmacokinetics of varenicline have been investigated in pediatric patients aged 12 to 17 years old (inclusive) and were approximately dose-proportional over the 0.5 mg to 2 mg daily dose range studied. Steady-state systemic exposure in adolescent patients of bodyweight >55 kg, as assessed by AUC (0–24), was comparable to that noted for the same doses in the adult population. When 0.5 mg BID was given, steady-state daily exposure of varenicline was, on average, higher (by approximately 40%) in adolescent patients with bodyweight ≤ 55 kg compared to that noted in the adult population.

Renal Impairment

Varenicline pharmacokinetics were unchanged in subjects with mild renal impairment (estimated creatinine clearance >50 mL/min and ≤80 mL/min). In subjects with moderate renal impairment (estimated creatinine clearance ≥30 mL/min and ≤50 mL/min), varenicline exposure increased 1.5-fold compared with subjects with normal renal function (estimated creatinine clearance >80 mL/min). In subjects with severe renal impairment (estimated creatinine clearance <30 mL/min), varenicline exposure was increased 2.1-fold. In subjects with end-stage-renal disease (ESRD) undergoing a three-hour session of hemodialysis for three days a week, varenicline exposure was increased 2.7-fold following 0.5 mg once daily administration for 12 days. The plasma Cmax and AUC of varenicline noted in this setting were similar to those of healthy subjects receiving 1 mg twice daily [see Dosage and Administration (2.2), Use in Specific Populations (8.6)]. Additionally, in subjects with ESRD, varenicline was efficiently removed by hemodialysis [see Overdosage (10)].

Hepatic Impairment

Due to the absence of significant hepatic metabolism, varenicline pharmacokinetics should be unaffected in patients with hepatic impairment.

Drug-Drug Interactions

In vitro studies demonstrated that varenicline does not inhibit the following cytochrome P450 enzymes (IC50 >6400 ng/mL): 1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4/5. Also, in human hepatocytes in vitro, varenicline does not induce the cytochrome P450 enzymes 1A2 and 3A4.

In vitro studies demonstrated that varenicline does not inhibit human renal transport proteins at therapeutic concentrations. Therefore, drugs that are cleared by renal secretion (e.g., metformin [see below]) are unlikely to be affected by varenicline.

In vitro studies demonstrated the active renal secretion of varenicline is mediated by the human organic cation transporter OCT2. Co-administration with inhibitors of OCT2 (e.g., cimeditine [see below]) may not necessitate a dose adjustment of Chantix as the increase in systemic exposure to Chantix is not expected to be clinically meaningful. Furthermore, since metabolism of varenicline represents less than 10% of its clearance, drugs known to affect the cytochrome P450 system are unlikely to alter the pharmacokinetics of Chantix [see Clinical Pharmacology (12.3)]; therefore, a dose adjustment of Chantix would not be required.

Drug interaction studies were performed with varenicline and digoxin, warfarin, transdermal nicotine, bupropion, cimetidine, and metformin. No clinically meaningful pharmacokinetic drug-drug interactions have been identified.

Metformin

When co-administered to 30 smokers, varenicline (1 mg twice daily) did not alter the steady-state pharmacokinetics of metformin (500 mg twice daily), which is a substrate of OCT2. Metformin had no effect on varenicline steady-state pharmacokinetics.

Cimetidine

Co-administration of an OCT2 inhibitor, cimetidine (300 mg four times daily), with varenicline (2 mg single dose) to 12 smokers increased the systemic exposure of varenicline by 29% (90% CI: 21.5%, 36.9%) due to a reduction in varenicline renal clearance.

Digoxin

Varenicline (1 mg twice daily) did not alter the steady-state pharmacokinetics of digoxin administered as a 0.25 mg daily dose in 18 smokers.

Warfarin

Varenicline (1 mg twice daily) did not alter the pharmacokinetics of a single 25 mg dose of (R, S)-warfarin in 24 smokers. Prothrombin time (INR) was not affected by varenicline. Smoking cessation itself may result in changes to warfarin pharmacokinetics [see Drug Interactions (7.2)].

Use with Other Drugs for Smoking Cessation

Bupropion: Varenicline (1 mg twice daily) did not alter the steady-state pharmacokinetics of bupropion (150 mg twice daily) in 46 smokers [see Drug Interactions (7.1)].

Nicotine replacement therapy (NRT): Although co-administration of varenicline (1 mg twice daily) and transdermal nicotine (21 mg/day) for up to 12 days did not affect nicotine pharmacokinetics, the incidence of adverse reactions was greater for the combination than for NRT alone [see Drug Interactions (7.1)].

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenesis

Lifetime carcinogenicity studies were performed in CD-1 mice and Sprague-Dawley rats. There was no evidence of a carcinogenic effect in mice administered varenicline by oral gavage for 2 years at doses up to 20 mg/kg/day (47 times the maximum recommended human daily (MRHD) exposure based on AUC). Rats were administered varenicline (1, 5, and 15 mg/kg/day) by oral gavage for 2 years. In male rats (n = 65 per sex per dose group), incidences of hibernoma (tumor of the brown fat) were increased at the mid dose (1 tumor, 5 mg/kg/day, 23 times the MRHD exposure based on AUC) and maximum dose (2 tumors, 15 mg/kg/day, 67 times the MRHD exposure based on AUC). The clinical relevance of this finding to humans has not been established. There was no evidence of carcinogenicity in female rats.

Mutagenesis

Varenicline was not genotoxic, with or without metabolic activation, in the following assays: Ames bacterial mutation assay; mammalian CHO/HGPRT assay; and tests for cytogenetic aberrations in vivo in rat bone marrow and in vitro in human lymphocytes.

Impairment of Fertility

There was no evidence of impairment of fertility in either male or female Sprague-Dawley rats administered varenicline succinate up to 15 mg/kg/day (67 and 36 times, respectively, the MRHD exposure based on AUC at 1 mg twice daily). Maternal toxicity, characterized by a decrease in body weight gain, was observed at 15 mg/kg/day. However, a decrease in fertility was noted in the offspring of pregnant rats who were administered varenicline succinate at an oral dose of 15 mg/kg/day. This decrease in fertility in the offspring of treated female rats was not evident at an oral dose of 3 mg/kg/day (9 times the MRHD exposure based on AUC at 1 mg twice daily).

PRINCIPAL DISPLAY PANEL - 0.5 / 1 mg Tablet Starting Pack Carton

Contains:
1 Starting Week (0.5 mg* x 11 tablets)
3 Continuing Weeks (1 mg† x 42 tablets)

NDC 0069-0471-03
Rx only

Chantix®
(varenicline) TABLETS

STARTING MONTH BOX
(Your first 4 weeks)

Use the Starting Week (green) blister card
first when beginning to take Chantix.

ALWAYS DISPENSE WITH ENCLOSED MEDICATION GUIDE

What is Chantix?

Chantix (varenicline) is a smoking cessation medicine. It is used together with behavior modification and counseling support to help you stop smoking.

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

Important information

Chantix may cause changes in your thoughts or behavior. Stop using this medicine and call your doctor at once if you have: any mood or behavior changes, confusion, anxiety, panic attacks, hallucinations, extreme fear, or if you feel impulsive, agitated, aggressive, restless, hostile, depressed, hyperactive (mentally or physically), or have thoughts about suicide or hurting yourself.

Do not drink large amounts alcohol. Varenicline can increase the effects of alcohol or change the way you react to it.

What should I avoid while taking Chantix?

Do not drink large amounts alcohol while taking this medicine. Varenicline can increase the effects of alcohol or change the way you react to it. Some people taking this medicine have had unusual or aggressive behavior or forgetfulness while drinking alcohol.

Do not use other medicines to quit smoking, unless your doctor tells you to. Using Chantix while wearing a nicotine patch can cause unpleasant side effects.

This medicine may impair your thinking or reactions. You may also have mood or behavior changes when you quit smoking. Until you know how Chantix and the smoking cessation process are going to affect you, be careful if you drive or do anything that requires you to be cautious and alert.

What other drugs will affect Chantix?

After you stop smoking, the doses of your other medications may need to be adjusted. Tell your doctor about all other medicines you use, especially:

  • insulin;

  • a blood thinner such as warfarin (Coumadin, Jantoven); or

  • asthma medicine (theophylline and others).

This list is not complete. Other drugs may interact with varenicline, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

For the Consumer

Applies to varenicline: oral tablet

Along with its needed effects, varenicline (the active ingredient contained in Chantix) 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 while taking varenicline:

Less common
  • Difficult or labored breathing
  • hyperventilation
  • tightness in the chest
Incidence not known
  • Anger
  • anxiety
  • behavior changes
  • discouragement
  • feeling sad or empty
  • feelings of panic
  • irregular heartbeats
  • irritability
  • 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 of varenicline 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
  • bloated or full feeling
  • change in taste
  • difficulty having a bowel movement (stool)
  • dry mouth
  • excess air or gas in the stomach or intestines
  • general feeling of discomfort or illness
  • headache
  • lack or loss of strength
  • loss of taste
  • nausea
  • passing gas
  • stomach pain
  • trouble sleeping
  • unusual tiredness or weakness
Less common
  • Acid or sour stomach
  • belching
  • body aches or pain
  • chills
  • cough
  • decreased appetite
  • dizziness
  • ear congestion
  • fever
  • heartburn
  • increased appetite
  • indigestion
  • itching skin or rash
  • loss of appetite
  • loss of voice
  • nightmares
  • sleepiness or unusual drowsiness
  • sneezing or sore throat
  • stomach discomfort or upset
  • stuffy or runny nose
  • trouble concentrating
  • unusual drowsiness, dullness, or feeling of sluggishness
  • vomiting

Varenicline Pregnancy Warnings

Animal studies have failed to reveal evidence of teratogenicity. Animal studies have reported reduced fetal weights, decreased fertility in offspring, and increased auditory startle response. There are no controlled data in human pregnancy. AU TGA pregnancy category B3: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans. US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

Use is not recommended. AU TGA pregnancy category: B3 US FDA pregnancy category: C

Administrative Information

LactMed Record Number

784

Last Revision Date

20170905

Disclaimer

Information presented in this database is not meant as a substitute for professional judgment. You should consult your healthcare provider for breastfeeding advice related to your particular situation. The U.S. government does not warrant or assume any liability or responsibility for the accuracy or completeness of the information on this Site.

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