Drug reference

Nicotine

Smoking Cessation Aid

CDSCO approvedSchedule H

EXCRETION

—

not curated

INTERACTIONS

—

none in our sources

PREGNANCY

—

not curated

Mechanism

Nicotine binds to and activates nicotinic acetylcholine receptors (nAChRs), which are ligand-gated cation channels located at autonomic ganglia, the neuromuscular junction, and throughout the CNS. In the brain, it preferentially activates α4β2 nAChR subtypes on dopaminergic neurons in the ventral tegmental area, stimulating dopamine release in the nucleus accumbens — the neural substrate of its addictive properties. At low doses it stimulates ganglionic transmission; at high doses it produces depolarization block, causing ganglionic paralysis.

Indications

Nicotine dependenceSmoking cessationNicotine replacement therapy (to help people quit smoking)Potential benefits in Parkinson's diseasePotential benefits in schizophreniaPotential benefits in dementiaPotential benefits in depressionPotential benefits in ADHDShort-term nicotine replacement in tobacco abstinent subjects (smoking cessation, tobacco chewing cessation)

Dosing

Adult: effective dose and for the shortest time possible, with a regular review at least every 6 weeks. h In patients who have dementia with Lewy bodies or Parkinson’s disease dementia, antipsychotic drugs can worsen the motor features of the condition, and in some cases cause severe antipsychotic sensitivity reactions. See also management of psychotic symptoms in Parkinson’s disease p. 429.…

Pharmacokinetics

Half-life

About 2 h (following inhalation)

Bioavailability

1–3 mg systemically from average cigarette (can increase 3-fold with puffing/technique)

Protein binding

Readily absorbed from the respiratory tract, buccal membranes, and skin. Limited absorption from the stomach; intestinal absorption is far more efficient. Slower absorption from chewing tobacco.

Metabolism

Approximately 80–90% altered, mainly in the liver, but also in the kidney and lung

Excretion

Rapidly eliminated by the kidney; rate diminishes when urine is alkaline. Also excreted in milk of lactating women. Cotinine is the major metabolite.

Contraindications

Avoid alkaline solutions during gastric lavage for poisoning
Cardiac arrhythmias
Ischaemic heart disease

Side effects

Common

NauseaSalivationAbdominal painVomitingDiarrheaCold sweatHeadacheDizzinessDisturbed hearing and visionMental confusionMarked weaknessIrritabilityImpatienceHostilityAnxietyDysphoric or depressed moodDifficulty in concentratingRestlessnessDecreased heart rateIncreased appetite or weight gainDyspepsiaAbdominal crampsLoose motionsInsomniaFlu-like symptomsLocal irritation

Serious

Faintness
Prostration
Fall in blood pressure
Difficult breathing
Weak, rapid, and irregular pulse
Collapse
Terminal convulsions
Death (within a few minutes from respiratory failure, at acutely fatal doses of about 60 mg in adults)
Tolerance
Dependence
Vasospastic angina may be precipitated