How To Reduce Nausea From Chantix (Varenicline)

In our latest question and answer, the pharmacist discusses how to reduce nausea from the smoking cessation medication Chantix (Varenicline).

How To Reduce Nausea From Chantix (Varenicline)
Jun 20, 2018

Noddy asked

I was wondering whether I could reduce my dosage of Chantix, 1mg. I have been using it for a month now - with great success - but the severe nausea is really getting to me. Could I potentially take just one tablet daily instead of 2?

Answer

NauseaChantix (varenicline) is a smoking cessation drug that is very effective in reducing nicotine cravings and assisting individuals to quit smoking. However, it associated with various gastrointestinal side effects such as nausea, vomiting and cramping that can make the medication difficult to tolerate.

Nausea From Chantix

Nausea is the most frequently reported adverse effect of Chantix, but is generally considered mild to moderate in severity. However, some individuals experience more severe cases of nausea that persist for several months and one study reported nausea of a side effect in nearly 40% of individuals taking the medication. Other gastrointestinal side effects that were reported include:

  • Abdominal pain
  • Fatulence
  • Heartburn
  • Vomiting 
  • Constipation
  • Appetite stimulation 
  • Decreased appetite 

The average drop-out rate for clinical trial participants who took Chantix was 3%, not an insignificant number. Fortunately, there are a few things you can do to reduce the nausea caused by Chantix.

Reducing Nausea From Chantix

Chantix

Tapering To Begin Therapy

First and foremost, if you are just starting Chantix, it is important to start with the Chantix titration packs, which start at a low dose of the drug and increase to the maintenance dose of 1mg twice daily.  It has been well documented that titration of Chantix greatly reduces the incidence of nausea and therefore, starting with the Chantix titration pack (also known as Chantix Starting Month) is the recommended course of action.


Taking Chantix After Food

Chantix is always recommended to be taken after food, with a full glass of water, to reduce nausea. It is especially important to take the medication after food, not with . Be sure to take it with food that you know you tolerate well. Generally, avoid foods that are high in fat and protein, as these can sometimes cause indigestion, which could exacerbate nausea from Chantix. Also, be sure to avoid carbonated beverages like beer and soda.


Dose Reduction

If you are already at the recommended maintenance dose of Chantix and taking the medication after food isn't helping, the prescribing information recommends a dose reduction for individuals experiencing severe nausea, but this should only be done after discussing the situation with your doctor. Per the prescribing information:

Approximately 3% of patients treated with CHANTIX 1 mg twice daily in studies involving 12 weeks of treatment discontinued treatment prematurely because of nausea. For patients with intolerable nausea, a dose reduction should be considered.
A dose reduction means a decrease from the usual 1mg twice daily. There is little data on what exactly your dose should be reduced to, but historically, a reduction of 0.5mg per dose has been used. One example is instead of 1mg twice daily, decrease to:

  • 1mg in the morning
  • 0.5mg in the evening

If that still is not better tolerated, your doctor may recommend a further dose reduction to:

  • 0.5mg in the morning
  • 0.5mg in the evening

It typically isn't recommended to reduce the dosage frequency as the medication may not last long enough with a single daily dose to reduce nicotine cravings all day.

Summary

  • Chantix is well known to cause nausea, with an incidence rate of nearly 40%.
  • Always initiate therapy with Chantix by starting with the 'Starting Month' titration pack, and slowly increasing your dose over time to significantly reduces nausea.
  • Be sure to always take Chantix after food, with a full glass of water. Avoid foods and drinks that you know you do not tolerate well.
  • A dosage reduction should be considered if you still cannot tolerate Chantix. Be sure to speak with your doctor before reducing your dose.

Ready for a more personal experience with your meds?