Home Drug Guide Varenicline Tartrate

Drug Guide

Generic Name

Varenicline Tartrate

Brand Names Chantix, Tyrvaya

Classification

Therapeutic: Smoking Cessation Aid

Pharmacological: Partial Nicotinic Acetylcholine Receptor Agonist

FDA Approved Indications

Smoking cessation in adults

Mechanism of Action

Varenicline selectively binds to alpha4beta2 nicotinic acetylcholine receptors in the brain, reducing cravings and withdrawal symptoms by partial stimulation and decreasing the rewarding effects of nicotine from tobacco products.

Dosage and Administration

Adult: Start at 0.5 mg once daily for 3 days, then 0.5 mg twice daily for 4 days, then increase to 1 mg twice daily. Continue for 12 weeks or as prescribed.

Pediatric: Not approved for pediatric use.

Geriatric: Use with caution; no specific dose adjustment, but assess renal function.

Renal Impairment: Reduce dose in patients with kidney impairment: 0.5 mg once daily for severe impairment (eGFR < 30 mL/min).

Hepatic Impairment: No dosage adjustment necessary.

Pharmacokinetics

Absorption: Well absorbed orally, peak plasma concentrations in about 3 hours.

Distribution: Minimal protein binding (~20%).

Metabolism: Not extensively metabolized; mainly excreted unchanged.

Excretion: Renal excretion. Primary route of elimination.

Half Life: Approx. 24 hours.

Contraindications

Hypersensitivity to varenicline or any component of the formulation.

Precautions

History of psychiatric illness, suicidal ideation, or depression; monitor mental health.
Patients with renal impairment; dose adjustment required.
Advise patients to report neuropsychiatric symptoms.

Adverse Reactions - Common

Nausea (Common)
Insomnia (Common)
Vivid dreams (Common)
Headache (Common)

Adverse Reactions - Serious

Neuropsychiatric events, including depression, agitation, suicidal thoughts (Less common but serious)
Seizures (Rare)

Drug-Drug Interactions

Other medications that affect CNS, sedatives, alcohol, drugs affecting renal function.

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Assess mental health status and substance use history before starting and periodically during treatment.

Diagnoses:

Risk for depression or suicidal ideation.
Noncompliance.

Implementation: Counsel patients on medication adherence, advise to report neuropsychiatric symptoms, and support smoking cessation.

Evaluation: Evaluate smoking abstinence, monitor side effects, and mental health status.

Patient/Family Teaching

Do not abruptly stop medication.
Report neuropsychiatric symptoms immediately.
Use in combination with behavioral therapies for best results.
Follow dosing schedule closely.

Special Considerations

Black Box Warnings:

Neuropsychiatric symptoms, including mood changes, agitation, depression, and suicidal thoughts.

Genetic Factors: Not specifically genetic-dependent.

Lab Test Interference: None known.

Overdose Management

Signs/Symptoms: Nausea, vomiting, headache, somnolence.

Treatment: Supportive care; no specific antidote. Dialysis may be considered in severe cases due to renal excretion.

Storage and Handling

Storage: Store at room temperature (20°C to 25°C). Keep container tightly closed.

Stability: Stable under recommended storage conditions.