What injectable medications are available for smoking cessation?

Injectable Medications for Smoking Cessation

Currently, there are no FDA-approved injectable medications specifically designed for smoking cessation. The primary pharmacotherapies recommended for smoking cessation are oral medications (varenicline, bupropion) and various forms of nicotine replacement therapy (patches, gum, lozenges, nasal spray, and inhaler) 1.

First-Line Pharmacotherapy Options

Preferred Primary Therapies

• Combination Nicotine Replacement Therapy (NRT): Nicotine patch plus a short-acting NRT (lozenge, gum, inhaler, or nasal spray) for 12 weeks minimum 1
• Varenicline: Oral medication taken for 12 weeks minimum 1, 2

Secondary Option

• Bupropion (with or without NRT): Oral antidepressant medication used for 7-12 weeks 1

Standard Dosing Information

Combination NRT

• 21 mg patch plus short-acting NRT for breakthrough cravings 1
• For patients not responding to standard dose, consider increasing to 35 or 42 mg patch 1
• Blood nicotine levels from NRT are significantly less than from smoking cigarettes 1

Varenicline

• Initiate 1-2 weeks before quit date 1
• Days 1-3: 0.5 mg orally once daily 1
• Days 4-7: 0.5 mg orally twice daily 1
• Weeks 2-12: 1 mg orally twice daily if tolerated 1
• Demonstrated superior efficacy (21.8% quit rate) compared to bupropion (16.2%) and nicotine patch (15.7%) in direct comparison trials 2

Bupropion

• Initiate 1-2 weeks before quit date 1
• Days 1-3: 150 mg orally once daily 1
• Day 4-12 weeks: 150 mg orally twice daily if tolerated 1
• Maximum 300 mg per day 1

Important Clinical Considerations

Efficacy

• Combined pharmacotherapy and behavioral support significantly increases smoking cessation success compared to minimal intervention (RR 1.83,95% CI 1.68-1.98) 3
• The EAGLES trial showed varenicline had the highest 6-month quit rate (21.8%) compared to bupropion (16.2%) and nicotine patch (15.7%) 2

Treatment Duration

• Minimum of 12 weeks of combination NRT or varenicline is recommended for initial quit attempts 1
• Therapy may be extended to promote continued cessation (6 months to 1 year) 1
• Prescribe for shorter durations initially and only renew if quit attempt is continuing 1

Follow-up Recommendations

• Follow-up within 2 weeks after starting pharmacotherapy (can be extended to 3 weeks to coordinate with regular appointments) 1
• Additional periodic follow-up during therapy (at minimum 12-week intervals) 1
• Track smoking reduction attempts and consider switching pharmacotherapy if progress stalls 1

Side Effects and Contraindications

• Varenicline: Monitor for nausea (common) and neuropsychiatric issues; contraindicated for patients with brain metastases due to seizure risk 1
• Bupropion: Monitor for neuropsychiatric issues; contraindicated for patients with seizure risks, those taking MAO inhibitors, or those with closed-angle glaucoma 1
• NRT: Generally well-tolerated; nicotine toxicity is rare and transient 1

Emerging Injectable Options

While not yet FDA-approved for smoking cessation, research is ongoing into:

• Nicotine vaccines: Show promise for relapse prevention by producing antibodies that bind to nicotine in the bloodstream, preventing it from reaching the brain 4, 5

Clinical Algorithm for Smoking Cessation Treatment

1. Assess smoking status and nicotine dependence in all patients 1
2. Start with combination NRT or varenicline as first-line therapy 1, 2
3. If initial therapy fails, switch to the other primary option before trying bupropion 1
4. Combine pharmacotherapy with behavioral support for optimal results 2, 3
5. Provide follow-up within 2-3 weeks of starting therapy 1
6. Consider extending therapy duration for patients who successfully quit to prevent relapse 1

Remember that nicotine withdrawal symptoms typically peak within 1-2 weeks of quitting and then subside. Encourage continued therapy even through brief slips, as patients who don't quit immediately may succeed later after withdrawal symptoms diminish 1.