Can varenicline (Chantix) be used in patients with bipolar 2 disorder?

Varenicline Use in Bipolar 2 Disorder: Safety Considerations and Recommendations

Varenicline should be used with caution in patients with bipolar 2 disorder, with close monitoring for mood changes and neuropsychiatric symptoms, but it remains a viable option when the benefits of smoking cessation outweigh the potential risks.

Safety Profile in Psychiatric Populations

The safety of varenicline in patients with psychiatric disorders has been extensively studied:

• The EAGLES trial (n=8,144), a large double-blind randomized controlled trial, found no significant increase in neuropsychiatric events for varenicline compared to nicotine patch or placebo in patients with psychiatric disorders 1.

• A 2015 systematic review and meta-analysis of 39 randomized controlled trials found no evidence that varenicline increases risk of suicide, suicidal ideation, depression, or death 1.

• A specific randomized, double-blind, placebo-controlled study in bipolar disorder (n=60) demonstrated that varenicline was effective for smoking cessation (48.4% quit rate vs 10.3% with placebo) without significant destabilization of mood 2.

Risk Considerations for Bipolar 2 Disorder

Despite the generally favorable safety profile, several case reports highlight potential risks:

• Individual case reports document varenicline-induced mania in patients with bipolar disorder 3, 4.

• A recent case report (2023) described auditory hallucinations in a young female with bipolar I disorder after starting varenicline 5.

• Abnormal dreams occurred significantly more often with varenicline (61.3%) compared to placebo (31%) in bipolar patients 2.

Clinical Approach to Varenicline Use in Bipolar 2 Disorder

Pre-Treatment Assessment

• Ensure the patient is clinically stable with well-controlled bipolar symptoms
• Review current medications for potential interactions
• Assess suicide risk and history of manic/hypomanic episodes

Monitoring Protocol

1. Start with standard varenicline dosing:

   • Days 1-3: 0.5 mg once daily
   • Days 4-7: 0.5 mg twice daily
   • Weeks 2-12: 1 mg twice daily (if tolerated) 1

2. Schedule follow-up within 2 weeks of starting treatment 1

3. Monitor specifically for:

   • Emergence of hypomanic symptoms
   • Changes in sleep patterns
   • Abnormal dreams
   • Suicidal ideation
   • Mood instability

Alternative Options

If varenicline is contraindicated or poorly tolerated:

• Combination nicotine replacement therapy (nicotine patch + short-acting NRT) is equally effective as varenicline 1
• Bupropion should be used with extreme caution in bipolar disorder due to risk of mood destabilization 1, 6

Practical Considerations

• Treatment Duration: Standard treatment is 12 weeks, but may be extended to 6 months-1 year to promote continued cessation 1

• Medication Adjustments: Consider dose adjustments if side effects occur but efficacy is noted 1

• Warning Signs: Discontinue varenicline immediately if the patient develops:

  • Increased mood lability
  • New or worsening suicidal ideation
  • Signs of hypomania or mania
  • Psychotic symptoms

Common Pitfalls to Avoid

1. Failure to monitor: Not scheduling frequent follow-ups during the initial treatment period

2. Overlooking drug interactions: Not considering potential interactions with mood stabilizers

3. Ignoring early warning signs: Dismissing subtle mood changes as normal nicotine withdrawal

4. Inadequate patient education: Not informing patients about potential neuropsychiatric symptoms to report

5. Abrupt discontinuation: Not providing a tapering schedule if discontinuation is needed

While varenicline carries some risk in bipolar disorder, the significant mortality benefit from smoking cessation often outweighs these risks when proper monitoring is in place. The decision should be made with full consideration of the patient's clinical stability, support system, and willingness to adhere to close follow-up.