What varenicline (Chantix) tablet pack sizes are available and how many tablets are needed for the standard 12‑week smoking‑cessation regimen, including adjustments for moderate renal impairment?

Varenicline Package Sizes and Tablet Requirements

For the standard 12-week smoking cessation regimen, patients require 53 tablets for the initial titration week (starter pack) plus 154 tablets for the remaining 11 weeks of maintenance dosing, totaling 207 tablets; patients with moderate renal impairment (creatinine clearance 30-50 mL/min) use the same standard dosing and tablet count, while those with severe renal impairment (creatinine clearance <30 mL/min) require only 84 tablets maximum for 12 weeks at the reduced dose of 0.5 mg twice daily. 1, 2

Standard Dosing Regimen and Tablet Count

Initial Titration (Week 1)

• Days 1-3: 0.5 mg once daily = 3 tablets 1, 2
• Days 4-7: 0.5 mg twice daily = 8 tablets 1, 2
• Total starter pack: 11 tablets (though the NCCN references a 53-tablet starter pack that includes the first 4 weeks) 1

Maintenance Phase (Weeks 2-12)

• Weeks 2-12: 1 mg twice daily = 154 tablets (11 weeks × 14 tablets/week) 1, 2
• Total for standard 12-week course: 207 tablets 1, 2

Extended Treatment Option

• For patients who successfully quit during the initial 12 weeks, an additional 12-week course (total 24 weeks) significantly increases long-term abstinence rates 1, 2
• Additional tablets needed: 168 tablets (12 weeks × 14 tablets/week at 1 mg twice daily) 1
• Total for 24-week regimen: 375 tablets 1

Available Tablet Strengths

Varenicline is available in two strengths: 2

• 0.5 mg tablets: White to off-white film-coated, capsular biconvex tablets 2
• 1 mg tablets: Light blue film-coated, capsular biconvex tablets 2

Dosing Adjustments for Renal Impairment

Mild to Moderate Renal Impairment (CrCl ≥30 mL/min)

• No dose adjustment required 2, 3
• Use standard 207-tablet regimen for 12 weeks 2

Severe Renal Impairment (CrCl <30 mL/min)

• Starting dose: 0.5 mg once daily 2
• Maximum dose: 0.5 mg twice daily (if tolerated) 2
• Tablet requirement: 84 tablets maximum for 12 weeks (if titrated to twice daily dosing) 2
• Renal function is the most clinically important factor affecting varenicline exposure, as the drug is almost exclusively excreted unchanged in urine 3

End-Stage Renal Disease (Hemodialysis)

• Maximum dose: 0.5 mg once daily (if tolerated) 2
• Tablet requirement: 84 tablets for 12 weeks 2

Critical Prescribing Considerations

Timing and Administration

• Begin varenicline 1-2 weeks before the target quit date 1, 2
• Take tablets after eating with a full glass of water to minimize nausea 2
• The titration schedule is specifically designed to minimize dose-dependent nausea, which occurs in 28-40% of patients 1

Mandatory Behavioral Counseling

• Varenicline must always be combined with behavioral counseling; pharmacotherapy alone is insufficient 1
• Minimum requirement: four counseling sessions during the 12-week treatment period, with the first session within 2-3 weeks of starting medication 1

Contraindications

• Absolute contraindication: History of serious hypersensitivity or skin reactions to varenicline 2
• Avoid in patients with: Brain metastases or active seizure disorder due to seizure risk 1

Common Pitfalls

• Clinicians should monitor renal function upon initiation, especially in patients with chronic kidney disease, as rare cases of acute renal failure have been reported 4
• Nausea typically peaks in weeks 1-2 and diminishes over time; reassure patients and consider flexible dosing (0.5 mg once daily to 1 mg twice daily) if intolerable 1
• No dose adjustment is needed for elderly patients or those with hepatic impairment, though monitoring renal function in elderly patients is prudent 2