Uses

What is varenicline used for?

Varenicline is commonly used to help people quit smoking

Varenicline may also be used for other conditions as determined by your healthcare provider.

Varenicline is also available as a nasal spray. See Tyrvaya for more information. 

How does varenicline work (mechanism of action)?

Varenicline helps people quit smoking by blocking the effect of nicotine on the brain. Nicotine is a substance found in cigarettes and other tobacco products that makes smoking feel good. Varenicline blocks this good feeling and can help prevent cravings to smoke cigarettes.   

How is varenicline supplied (dosage forms)?

Varenicline is available in the following dosage forms that are taken by mouth.

  • 0.5 mg oral tablets
  • 1 mg oral tablets

How should I store varenicline?

Varenicline should be stored at room temperature, between 68 F to 77 F (20 C to 25 C). It can be exposed to temperatures between 59 F to 86 F (15 C to 30 C), for shorter periods of time, such as when transporting it. Store in a cool, dry place.

Side Effects

What are the most common side effects of varenicline?

The most common side effects of varenicline are listed below. Tell your healthcare provider if you have any of these side effects that bother you.

  • Nausea
  • Trouble sleeping
  • Strange or vivid dreams
  • Constipation
  • Gas
  • Vomiting

There may be other side effects of varenicline that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of varenicline?

While less common, the most serious side effects of varenicline are described below, along with what to do if they happen.

Severe Allergic Reactions. Varenicline may cause allergic reactions, which can be serious. Stop taking varenicline and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Seizures. Some people who have taken varenicline have reported having seizures. There are many different types of seizures and some of them are not easy to recognize. Stop taking varenicline and call your healthcare provider if you experience any of the following signs that a seizure is happening or could happen.

  • Muscle twitching, jerking, spasms, tremors, or other uncontrolled movements
  • Stiffening of your arms and legs
  • Feeling anxious, nervous, confused, or a sense of dread
  • Feeling dizzy or lightheaded
  • Falling or losing consciousness

New or Worse Heart or Blood Vessel Problems. Varenicline can cause new or worsening heart or blood vessel problems, including heart attacks and stroke. This risk is mainly in people with existing heart or blood vessel problems. Tell your healthcare provider right away if you have any changes in symptoms. Get emergency help if you have any of the following symptoms of a heart attack or stroke.

  • Chest pain or pressure
  • Fast or abnormal heartbeat
  • Trouble breathing
  • Pain in your back, jaw, throat, or arm
  • Sweating, upset stomach, vomiting, or dizziness
  • Sudden weakness on one side of your body
  • Sudden and severe headache
  • Slurred speech or trouble understanding speech

Sleepwalking. Varenicline can cause sleepwalking. This may result in harm to yourself or other people or property. Stop taking varenicline and call your healthcare provider if you start sleepwalking. 

Serious Skin Reactions. Varenicline can cause severe skin reactions, including Stevens-Johnson Syndrome (SJS), that can lead to death if not treated. If you develop a rash, stop varenicline and call your healthcare provider right away. Get emergency help right away if you have any of the following symptoms of a severe skin reaction.

  • Painful red or purple skin that looks burned and peels off
  • Flat red rash or blisters on your skin, mouth, nose, and genitals
  • Red, painful, watery eyes

New or Worse Mental Health Problems. Varenicline may cause new or worse mental health problems. This risk is more common in people who have a history of mental health problems. These symptoms may also happen because of nicotine withdrawal. Stop taking varenicline and call your healthcare provider right away if you have any of the following symptoms.

  • Changes in mood or behavior 
  • Aggression
  • Hostility  
  • Agitation
  • Depressed mood 

Suicidal Thoughts or Actions. Varenicline may cause suicidal thoughts or actions in a small number of people. If you are about to harm yourself, call 911 or call or text 988, the Suicide & Crisis Lifeline. Call your healthcare provider right away if you have any of the following symptoms.

  • New or increased thoughts of suicide or death
  • Suicide attempt
  • New or increased feelings of anxiety, depression, or other unusual changes in mood or behavior

Angioedema. Varenicline may cause a rare reaction called angioedema. The usual symptoms of this reaction include swelling of the lips, face, tongue, or throat. Stop taking the medicine and contact your healthcare provider if you have this type of swelling. If you are having trouble breathing, get medical attention right away.

Warnings & Precautions

Who should not use varenicline?

Allergies to Ingredients. People who are allergic to any of the following should not take varenicline.

  • Chantix
  • Tyrvaya
  • Varenicline
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific varenicline products they stock.

What should I know about varenicline before using it?

Do not take varenicline unless it has been prescribed to you by a healthcare provider. Take it as prescribed.

Do not share varenicline with other people, even if they have the same condition as you. It may harm them.

Keep varenicline out of the reach of children.

Varenicline should be taken after eating and with a full glass of water.

Make sure that you understand how to properly take varenicline. If you have any questions, talk to your healthcare provider.

Varenicline can affect your alertness or coordination. There are reports of people having traffic accidents or other injuries while taking varenicline due to side effects like dizziness, sleepiness, and difficulty focusing. Do not drive or do other activities that require alertness or coordination until you know how varenicline affects you. 

When you try to quit smoking, you may have symptoms of nicotine withdrawal. This can happen with or without varenicline. The most common symptoms of nicotine withdrawal are listed below.

  • Craving to smoke 
  • Anxiety and depression
  • Restlessness and trouble sleeping
  • Irritability, frustration, or anger
  • Difficulty concentrating
  • Decreased heart rate 
  • Increased appetite and weight gain 

What should I tell my healthcare provider before using varenicline?

Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if varenicline is right for you.

In particular, make sure that you discuss any of the following.

Other Treatments to Help Quit Smoking. Tell your healthcare provider if you are using nicotine patches to help quit smoking. Taking varenicline while using a nicotine patch can increase the risk of the following side effects. 

  • Nausea
  • Vomiting
  • Headache
  • Dizziness
  • Upset stomach 
  • Tiredness

Kidney Problems. If there is a concern about the health of your kidneys, your healthcare provider may do tests to determine if you will need a lower dose of this medicine.

Seizures. Varenicline may increase the risk of or worsen seizures in certain people who have a history of seizures. Tell your doctor if you have a history of seizures and about any medicines you take for seizures.

Heart or Blood Vessel Problems. Varenicline may increase the risk of a new or worse heart or blood vessel problem, especially if you already have a heart or blood vessel problem. 

Mental Health Problems. Tell your healthcare provider about your recent and current mental health problems, especially if you have ever had depression. You should also tell your healthcare provider about any symptoms you had during other times when you tried to quit smoking.

Pregnancy. It is not known if or how varenicline could affect pregnancy or harm an unborn baby. Tell your healthcare provider if you are or plan to become pregnant. Your healthcare provider will advise you if you should take varenicline while you are pregnant or trying to get pregnant.

Breastfeeding. It is not known if varenicline passes into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed. Your healthcare provider will advise you if you should take varenicline while breastfeeding. If you breastfeed while taking varenicline, watch for symptoms of a seizure in your baby and feeding problems, such as spitting up more than usual.

Other Medicines and Supplements. Quitting smoking may interact with other medicines and supplements. Before quitting smoking, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Interactions

Does varenicline interact with foods or drinks?

There are no known interactions between varenicline and foods or nonalcoholic drinks.

Limit the amount of alcohol you drink while taking varenicline. Varenicline may affect your ability to tolerate alcohol. Taking varenicline and drinking alcohol can cause the following feelings.

  • Increased drunkenness (intoxication)
  • Unusual or sometimes aggressive behavior
  • No memory of things that have happened

Does varenicline interact with other medicines (drug interactions)?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any other medicine to help you quit smoking, such as a nicotine patch, before using varenicline.

When you quit smoking, this can affect other medicines and their doses. This can happen with or without taking varenicline. Make sure to tell your healthcare provider if you are quitting smoking. Examples of medicines that might need changes to their doses if you quit smoking are listed below.

  • Theophylline, which is a medicine used for breathing conditions 
  • Warfarin (Coumadin, Jantoven), which is a blood thinner  
  • Insulin, which is a medicine used to lower blood sugar in diabetes 

This may not be a complete list of medicines that can interact with varenicline. Always check with your healthcare provider.

Does Varenicline interact with other drugs you are taking?
Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much varenicline?

If you or someone else has used too much varenicline, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of varenicline?

If you miss a dose of varenicline, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.

Drug Survey

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