Nicotine Addiction

BASICS

Nicotine addiction is marked by compulsive use, lack of control, withdrawal, and continued use despite known harm.

2019: 50.6 million U.S. adults (20.8%) used tobacco; 14% smoked cigarettes; 4.5% used e-cigarettes.
Pregnancy: 7.2% of women who gave birth in 2016 smoked during pregnancy.
Youth: In 2020, 19.6% of high school and 4.7% of middle school students used e-cigarettes (3.6 million youth).
Higher rates in: American Indian/Alaska Native, LGBTQ, lower education/income, uninsured, disabled, anxiety disorders.

Nicotine acts on nicotinic acetylcholine receptors (nAChRs)—modulates dopamine, glutamate, GABA, serotonin, NE, and ACh.
Results in euphoria, anxiety reduction, cognitive enhancement.
Tolerance/dependence: Upregulation of nAChRs.
Genetics: Polymorphisms in nAChR genes (increased susceptibility).
Metabolism: CYP2A6; fast metabolizers = more intense withdrawal, lower quit rates.
Withdrawal: Corticotropin-releasing factor in amygdala → anxiety/stress.

Placenta previa, abruptio placentae, preterm labor, low birth weight, IUGR, SIDS, asthma, neurocognitive problems.

USPSTF Recommendations:
Screen all adults for tobacco use, provide cessation interventions if positive.
Screen pregnant women for tobacco use, provide tailored counseling.
Prevent initiation among youth (education, brief counseling).

Lung cancer screening: Annual low-dose CT for adults 50–80 y/o, ≥20 pack-years, current/recent smokers (not life-limited).
Spirometry and routine chest x-rays NOT recommended for screening.

FDA-approved:
NRT (patch, gum, lozenge, inhaler, nasal spray)
Bupropion SR
Varenicline (most effective)
Duration: >12 weeks recommended.
Varenicline: Partial nAChR agonist, start even if not ready to quit; preferred over patch or bupropion.
Starter pack: 0.5 mg/d x3d, then 0.5 mg BID x4d, then 1 mg BID.
Maintenance: 1 mg BID x12w; may extend another 12w.
Monitor for: Vivid dreams, sleepwalking, depression, suicidal ideation.
Bupropion SR: NDRI antidepressant; contraindicated in seizure risk, eating disorders, recent MAOI.
Start 1 week before quit date. 150 mg/d x3d, then 150 mg BID x7–12w.
Nortriptyline: Off-label, tricyclic antidepressant; contraindicated in cardiac/ocular disease.
25 mg/d, increase to 75–100 mg/d x12w; set quit date 2–4w after start.
NRT:
Patch dosing based on cigarettes/day; adjust and taper over weeks.
Gum/Lozenge: 2 mg if >30 min to first cigarette; 4 mg if <30 min.
Combination NRT (patch + short-acting): More effective than single NRT.
Avoid NRT in recent MI, unstable angina, serious arrhythmia, age <18 y.
E-cigarettes: Insufficient evidence for efficacy/safety; NOT recommended in pregnancy.

Follow-up: 1–2 weeks after starting, then periodically (especially 1st 3 months).
Withdrawal monitoring: Appetite/weight gain, mood changes, insomnia, irritability, anxiety, concentration issues.
Pharmacotherapy generally for 3 months.

50% of smokers will die from tobacco-related illness.
Risk reduction: 50% reduction in CAD risk at 1 year; 50% reduction in head/neck cancers at 2–5 years; 50% reduction in lung cancer mortality by 10 years; stroke risk returns to nonsmoker level by 2–5 years.
Relapse: 22% relapse within 3 months; multiple attempts often needed.
Social support increases quit success.

COPD, Cancers (lung, head/neck, GU, GI), atherosclerosis, PUD, periodontal disease, osteoporosis/hip fracture (women), delayed wound healing, pregnancy complications, others.

Nicotine dependence = chronic disease; expect multiple interventions/attempts.
Choose cessation therapy based on patient risk/preference; no single best drug.
Tobacco product landscape is evolving (smoked, smokeless, electronic).
E-cigarettes are NOT safe alternatives for youth, pregnancy, or long-term cessation.