(var EN i kleen)
- Varenicline Tartrate
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Chantix: 0.5 mg, 1 mg
Chantix Continuing Month Pak: 1 mg
Chantix Starting Month Pak: 0.5 mg x 11 & 1 mg x 42
Brand Names: U.S.
- Chantix Continuing Month Pak
- Chantix Starting Month Pak
- Partial Nicotine Agonist
- Smoking Cessation Aid
Partial neuronal α4 β2 nicotinic receptor agonist; prevents nicotine stimulation of mesolimbic dopamine system associated with nicotine addiction. Also binds to 5-HT3 receptor (significance not determined) with moderate affinity. Varenicline stimulates dopamine activity but to a much smaller degree than nicotine does, resulting in decreased craving and withdrawal symptoms.
Well absorbed; unaffected by food
Minimal (<10% of clearance is through metabolism)
Urine (92% as unchanged drug)
Time to Peak
Plasma: ~3 to 4 hours
Special Populations: Renal Function Impairment
Moderate Renal Function Impairment (CrCl ≥30 to ≤50 mL/minute)
Drug exposure increased 1.5-fold.
Severe Renal Function Impairment (CrCl <30 mL/minute)
Drug exposure increased 2.1-fold.
End-Stage Renal Disease
Drug exposure increased 2.7-fold.
Moderate renal impairment (CrCl ≥30 to ≤50 mL/minute): Drug exposure increased 1.5-fold.
Severe renal impairment (CrCl <30 mL/minute): Drug exposure increased 2.1-fold.
End-stage renal disease requiring hemodialysis: Drug exposure increased 2.7-fold.
Use: Labeled Indications
Smoking cessation: As an aid to smoking cessation treatment
Serious hypersensitivity reactions or skin reactions to varenicline or any component of the formulation
Smoking cessation: Adults: Oral:
Days 1 to 3: 0.5 mg once daily
Days 4 to 7: 0.5 mg twice daily
Maintenance (≥ Day 8):
U.S. labeling: 1 mg twice daily for 11 weeks
Canadian labeling: 0.5 to 1 mg twice daily for 11 weeks
Note: Start 1 week before target quit date. Alternatively, patients may consider setting a quit date up to 35 days after initiation of varenicline and then quit smoking between 8 to 35 days of treatment (some data suggest that an extended pretreatment regimen may result in higher abstinence rates [Hajek, 2011]). If patient successfully quits smoking at the end of the 12 weeks, may continue for another 12 weeks to help maintain success. Patients who are motivated to quit and do not succeed in stopping smoking during prior therapy, or who relapse after treatment, should be encouraged to make another attempt with varenicline once factors contributing to the failed attempt have been identified and addressed.
Dosage adjustment for toxicity: Patients who cannot tolerate adverse events may require temporary (or permanent) reduction in dose.
Dosage adjustment in renal impairment:
CrCl ≥30 mL/minute: No dosage adjustment necessary.
CrCl <30 mL/minute: Initial: 0.5 mg once daily; maximum dose: 0.5 mg twice daily
End-stage renal disease (ESRD) (receiving hemodialysis): Maximum dose: 0.5 mg once daily
Dosage adjustment in hepatic impairment: No dosage adjustment necessary.
Administer after eating and with a full glass of water.
Take after eating and with a full glass of water to decrease gastric upset.
Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F).
Alcohol (Ethyl): Varenicline may enhance the adverse/toxic effect of Alcohol (Ethyl). Specifically, alcohol tolerance may be decreased and the risk for neuropsychiatric adverse effects may be increased. Monitor therapy
BuPROPion: May increase the serum concentration of OCT2 Substrates. Monitor therapy
H2-Antagonists: May increase the serum concentration of Varenicline. Management: Monitor for increased varenicline adverse effects with concomitant use of cimetidine or other H2-antagonists, particularly in patients with severe renal impairment. International product labeling recommendations vary. Consult appropriate labeling. Monitor therapy
Nicotine: Varenicline may enhance the adverse/toxic effect of Nicotine. Monitor therapy
Quinolone Antibiotics: May increase the serum concentration of Varenicline. Management: Monitor for increased varenicline adverse effects with concurrent use of levofloxacin or other quinolone antibiotics, particularly in patients with severe renal impairment. International product labeling recommendations vary. Consult appropriate labeling. Monitor therapy
Trimethoprim: May increase the serum concentration of Varenicline. Management: Monitor for increased varenicline adverse effects with concomitant use of trimethoprim, particularly in patients with severe renal impairment. International product labeling recommendations vary. Consult appropriate labeling. Monitor therapy
Central nervous system: Headache (15% to 19%), insomnia (10% to 19%), abnormal dreams (9% to 13%), irritability (11%), suicidal ideation (11%), depression (4% to 11%)
Gastrointestinal: Nausea (16% to 40%), vomiting (5% to 11%)
1% to 10%:
Cardiovascular: Angina pectoris (4%), chest pain (3%), peripheral edema (2%), myocardial infarction (≤1%)
Central nervous system: Agitation (7%), malaise (7%), sleep disorder (5%), tension (4%), drowsiness (3%), hostility (2% to 3%), lethargy (1% to 2%), nightmares (1% to 2%)
Dermatologic: Skin rash (3%)
Gastrointestinal: Flatulence (6% to 9%), constipation (5% to 8%), dysgeusia (5% to 8%), abdominal pain (7%), diarrhea (6%), xerostomia (6%), dyspepsia (5%), increased appetite (3% to 4%), anorexia (2%), gastroesophageal reflux disease (1%)
Respiratory: Upper respiratory tract infection (5% to 7%), dyspnea (2%), rhinorrhea (≤1%)
<1% (Limited to important or life-threatening): Acute renal failure, amnesia, anemia, atrial fibrillation, Bell's palsy, cataract (subcapsular), cerebrovascular accident, conjunctivitis, cor pulmonale, coronary artery disease, decreased visual acuity, diabetes mellitus, dissociative disorder, dysarthria, dysphagia, ECG abnormality, eczema, enterocolitis, erectile dysfunction, erythema multiforme, gallbladder disease, gastrointestinal hemorrhage, homicidal ideation, hyperhidrosis, hyperlipidemia, hypersensitivity, hypoglycemia, hypokalemia, intestinal obstruction, leukocytosis, loss of consciousness, lymphadenopathy, mania, Meniere's disease, migraine, multiple sclerosis, myositis, nephrolithiasis, nocturnal amblyopia, nystagmus, ophthalmic vascular disease, oral mucosa ulcer, osteoporosis, pancreatitis, panic, photophobia, psychomotor agitation, psychomotor retardation, psychosis, pulmonary embolism, restless leg syndrome, seizure, skin photosensitivity, splenomegaly, Stevens-Johnson syndrome, syncope, tachycardia, thrombocytopenia, thrombosis, thyroid disease, transient blindness, transient ischemic attacks, urinary retention, ventricular premature contractions
Concerns related to adverse effects:
• CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving). There have been postmarketing reports of traffic accidents, near-miss incidents in traffic, or other accidental injuries in patients taking varenicline.
• Hypersensitivity reactions: Postmarketing reports of hypersensitivity reactions (including angioedema) and rare cases of serious skin reactions (including Stevens-Johnson syndrome and erythema multiforme) have been reported. Patients should be instructed to discontinue use and contact healthcare provider if signs/symptoms occur.
• Nausea: Dose-dependent nausea may occur; both transient and persistent nausea has been reported. Dosage reduction may be considered for intolerable nausea.
• Neuropsychiatric effects: [U.S. Boxed Warning]: Serious neuropsychiatric events (including depression, suicidal thoughts, and suicide) have been reported with use; some cases may have been complicated by symptoms of nicotine withdrawal following smoking cessation. Smoking cessation (with or without treatment) is associated with nicotine withdrawal symptoms and the exacerbation of underlying psychiatric illness; however, some of the behavioral disturbances were reported in treated patients who continued to smoke. Neuropsychiatric symptoms (eg, mood disturbances, psychosis, hostility) have occurred in patients with and without pre-existing psychiatric disease; many cases resolved following therapy discontinuation although in some cases, symptoms persisted. Monitor all patients for behavioral changes and psychiatric symptoms (eg, agitation, depression, suicidal behavior, suicidal ideation); inform patients to discontinue treatment and contact their healthcare provider immediately if they experience any behavioral and/or mood changes.
• Cardiovascular events: Treatment may increase risk of cardiovascular events. A meta-analysis of 15 clinical trials, including a placebo-controlled trial in patients with stable cardiovascular disease, showed an increased incidence of major cardiovascular events (combined outcome of cardiovascular-related death, nonfatal MI, nonfatal stroke) in patients using varenicline compared with placebo. Cardiovascular events were uncommon in both the varenicline and placebo groups. These findings did not reach statistical significance, although data was consistent. Events occurred primarily in patients with known cardiovascular disease. The meta-analysis also showed a lower incidence of all-cause and cardiovascular mortality in varenicline-treated patients, although this was not statistically significant either.
• Psychiatric illness: Patients with preexisting psychiatric illness (eg, bipolar disorder, major severe depression, schizophrenia) were not studied in premarketing clinical trials; and limited safety data is available from postmarketing studies. Due to rare neuropsychiatric events, caution is warranted if treatment is initiated; worsening of psychiatric illness has been reported.
• Renal impairment: Use with caution in patients with renal impairment; dosage adjustment required with severe impairment.
• Seizures: Seizures have been reported in patients with or without a history of seizures. Seizures generally occurred within the first month of therapy. Consider the risks against the benefits before initiating in patients with a history of seizures or other factors that can lower the seizure threshold; discontinue use if seizures occur during therapy.
Concurrent drug therapy issues:
• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.
• Risk vs benefit: [U.S. Boxed Warning]: Before prescribing, the risks of serious neuropsychiatric events must be weighed against the immediate and long term benefits of smoking abstinence for each patient.
Monitor for behavioral changes and psychiatric symptoms (eg, agitation, depression, suicidal behavior, suicidal ideation).
Pregnancy Risk Factor
Adverse events have been observed in animal reproduction studies.
• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
• Patient may experience dizziness, fatigue, flatulence, insomnia, headache, nightmares, xerostomia, asthenia, dysgeusia, or constipation. Have patient report immediately to prescriber angina, dyspnea, strength differences from one side to another, difficulty speaking or thinking, change in balance, memory impairment, hallucinations, blurred vision, significant nausea, illogical thinking, or signs of Stevens-Johnson syndrome/toxic epidermal necrolysis (HCAHPS).
• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.
More about varenicline
- Other brands: Chantix