Questions About Cancer? 1-800-4-CANCER
  • Print
  • email
  • Facebook
  • Twitter
  • Google+
  • Pinterest

Table 5. Varenicline and Bupropion HCl

 Brand Dose Side Effects Warning/Precautiona 
RxChantix (varenicline)0.5 mg/d, days 1–3; 0.5 mg bid, days 4–7; then 1.0 mg bid through week 12Nausea, insomniaRisk of toxicity higher in patients with impaired renal function.
Not tested in children and pregnant women.
RxZyban (bupropion HCl)150 mg/d × 3 days, then increase to 300 mg/d × 7–12 weeksInsomnia, dry mouth, dizziness, rhinitisDo not take with Wellbutrin or Wellbutrin SR.
Higher incidence of seizures in patients treated for bulimia or anorexia.

bid = twice a day; HCl = hydrochloride; Rx = prescription; SR = sustained release.
aClinicians need to closely monitor all patients taking varenicline and bupropion hydrochloride (HCl). The premarketing smoking cessation studies of these medications excluded patients with serious psychiatric illness (e.g., schizophrenia, bipolar disorder, and major depressive disorder), suggesting that the safety of these medications for these patients has not been investigated.[15,20] Therefore, during smoking cessation, patients with preexisting psychiatric illness who are receiving varenicline and bupropion HCl for smoking cessation need to be especially monitored.


  1. CHANTIX (varenicline) Tablets. New York, NY: Pfizer Inc., 2013. Available online. Last accessed June 12, 2014. 

  2. U.S. Food and Drug Administration: Information for Healthcare Professionals: Varenicline (Marketed as Chantix) and Bupropion (Marketed as Zyban, Wellbutrin, and Generics). Rockville, Md: U.S. Food and Drug Administration, 2009. Available online. Last accessed June 12, 2014.