Overview
11 DESCRIPTION Varenicline tablets contain varenicline (as the tartrate salt), which is a partial nicotinic agonist selective for α 4 β 2 nicotinic acetylcholine receptor subtypes. Varenicline, as the tartrate salt, is a powder which is a white to off-white to slightly yellow solid with the following chemical name: 7,8,9,10-tetrahydro-6,10-methano-6 H -pyrazino[2,3- h][3]benzazepine, (2 R ,3 R...
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Varenicline binds with high affinity and selectivity at α4β2 neuronal nicotinic acetylcholine receptors. The efficacy of varenicline in smoking cessation is believed to be the result of varenicline’s activity at α4β2 sub-type of the nicotinic receptor where its binding produces agonist activity, while simultaneously preventing nicotine binding to these receptors. Electrophysiology studies in vitro and neurochemical studies in vivo have shown that varenicline binds to α4β2 neuronal nicotinic acetylcholine receptors and stimulates receptor-mediated activity, but at a significantly lower level than nicotine.
Indications
- 1 INDICATIONS AND USAGE Varenicline tablets are indicated for use as an aid to smoking cessation treatment. Varenicline tablets are a nicotinic receptor partial agonist indicated for use as an aid to smoking cessation treatment. ( 1 and 2.1 )
Common Doses
- 0.5 mg
- 1 mg
- 30 mL
Dosage
2 DOSAGE AND ADMINISTRATION Begin varenicline tablets dosing one week before the date set by the patient to stop smoking. Alternatively, the patient can begin varenicline tablets dosing and then quit smoking between days 8 and 35 of treatment. ( 2.1 ) Starting Week: 0.5 mg once daily on days 1 to 3 and 0.5 mg twice daily on days 4 to 7. ( 2.1 ) Continuing Weeks: 1 mg twice daily for a total of 12 weeks. ( 2.1 ) An additional 12 weeks of treatment is recommended for successful quitters to increase likelihood of long-term abstinence. ( 2.
Contraindications
- 4 CONTRAINDICATIONS Varenicline tablets are contraindicated in patients with a known history of serious hypersensitivity reactions or skin reactions to varenicline tablets. History of serious hypersensitivity or skin reactions to varenicline tablets. ( 4 )
Side Effects
- 6 ADVERSE REACTIONS The following serious adverse reactions were reported in postmarketing experience and are discussed in greater detail in other sections of the labeling: Neuropsychiatric Adverse Events including Suicidality [see Warnings and Precautions (5.1) ] Seizures [see Warnings and Precautions (5.2) ] Interaction with Alcohol [see Warnings and Precautions (5.3) ] Accidental Injury [see Warnings and Precautions (5.4) ] Cardiovascular Events [see Warnings and Precautions (5.5) ] Somnambulism [see Warnings and Precautions (5.
Interactions
- 7 DRUG INTERACTIONS Based on varenicline characteristics and clinical experience to date, varenicline has no clinically meaningful pharmacokinetic drug interactions [see Clinical Pharmacology (12.3) ]. Other Smoking Cessation Therapies: Safety and efficacy in combination with other smoking cessation therapies has not been established. Coadministration of varenicline and transdermal nicotine resulted in a high rate of discontinuation due to adverse events. ( 7.1 ) Effect of Smoking Cessation on Other Drugs: Pharmacokinetics or pharmacodynamics of certain drugs (e.g.