Chantix Side Effects

Generic Name: varenicline

Please note - some side effects for Chantix may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Side Effects of Chantix - for the Consumer

Chantix

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Chantix:

Constipation; gas; headache; increased appetite; nausea; stomach upset; taste changes; trouble sleeping; vivid, strange, or unusual dreams; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur when using Chantix:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, throat, or tongue; unusual hoarseness); behavior changes; chest pain; fainting; fast, slow, or irregular heartbeat; hallucinations; memory loss; new or worsening mental or mood problems (eg, aggression, agitation, anger, anxiety, depression, nervousness, thoughts of hurting other people); persistent trouble sleeping; red, swollen, blistered, or peeling skin; seizures; severe or persistent nausea; suicidal thoughts or actions; vision changes.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

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Chantix Side Effects - for the Professional

Chantix

The following serious adverse reactions were reported in postmarketing experience and are discussed in greater detail in other sections of the labeling:

• Neuropsychiatric symptoms and suicidality [see Boxed Warning and Warnings and Precautions (5.1)
• Angioedema and hypersensitivity reactions [see Warnings and Precautions (5.2)]
• Serious skin reactions [see Warnings and Precautions (5.3)]
• Accidental injury [see Warnings and Precautions (5.5)]

In the placebo-controlled studies, the most common adverse events associated with Chantix (>5% and twice the rate seen in placebo-treated patients) were nausea, abnormal (vivid, unusual, or strange) dreams, constipation, flatulence, and vomiting.

The treatment discontinuation rate due to adverse events in patients dosed with 1 mg twice daily was 12% for Chantix, compared to 10% for placebo in studies of three months' treatment. In this group, the discontinuation rates that are higher than placebo for the most common adverse events in Chantix-treated patients were as follows: nausea (3% vs. 0.5% for placebo), insomnia (1.2% vs. 1.1% for placebo), and abnormal dreams (0.3% vs. 0.2% for placebo).

Smoking cessation, with or without treatment, is associated with nicotine withdrawal symptoms and has also been associated with the exacerbation of underlying psychiatric illness.

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, the adverse reactions rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

During the premarketing development of Chantix, over 4500 subjects were exposed to Chantix, with over 450 treated for at least 24 weeks and approximately 100 for a year. Most study participants were treated for 12 weeks or less.

The most common adverse event associated with Chantix treatment is nausea, occurring in 30% of patients treated at the recommended dose, compared with 10% in patients taking a comparable placebo regimen [see Warnings and Precautions (5.6)].

Table 1 shows the adverse events for Chantix and placebo in the 12-week fixed dose studies with titration in the first week [Studies 2 (titrated arm only), 4, and 5]. Adverse events were categorized using the Medical Dictionary for Regulatory Activities (MedDRA, Version 7.1).

MedDRA High Level Group Terms (HLGT) reported in ≥ 5% of patients in the Chantix 1 mg twice daily dose group, and more commonly than in the placebo group, are listed, along with subordinate Preferred Terms (PT) reported in ≥ 1% of Chantix patients (and at least 0.5% more frequent than placebo). Closely related Preferred Terms such as 'Insomnia', 'Initial insomnia', 'Middle insomnia', 'Early morning awakening' were grouped, but individual patients reporting two or more grouped events are only counted once.

Table 1: Common Treatment Emergent AEs (%) in the Fixed-Dose, Placebo-Controlled Studies (HLGTs ≥ 5% of patients in the 1 mg BID Chantix Group and more commonly than placebo and PT ≥ 1% in the 1 mg BID Chantix Group, and 1 mg BID Chantix at least 0.5% more than Placebo)

SYSTEM ORGAN CLASS   High Level Group Term     Preferred Term	Chantix 0.5 mg BID N=129	Chantix 1 mg BID N=821	Placebo N=805
* Includes PTs Abdominal (pain, pain upper, pain lower, discomfort, tenderness, distension) and Stomach discomfort † Includes PTs Insomnia/Initial insomnia/Middle insomnia/Early morning awakening
GASTROINTESTINAL (GI)
GI Signs and Symptoms
Nausea	16	30	10
Abdominal Pain *	5	7	5
Flatulence	9	6	3
Dyspepsia	5	5	3
Vomiting	1	5	2
GI Motility/Defecation Conditions
Constipation	5	8	3
Gastroesophageal reflux disease	1	1	0
Salivary Gland Conditions
Dry mouth	4	6	4
PSYCHIATRIC DISORDERS
Sleep   Disorder/Disturbances
Insomnia †	19	18	13
Abnormal dreams	9	13	5
Sleep disorder	2	5	3
Nightmare	2	1	0
NERVOUS SYSTEM
Headaches
Headache	19	15	13
Neurological Disorders   NEC
Dysgeusia	8	5	4
Somnolence	3	3	2
Lethargy	2	1	0
GENERAL DISORDERS
General Disorders NEC
Fatigue/Malaise/Asthenia	4	7	6
RESPIR/THORACIC/MEDIAST
Respiratory Disorders NEC
Rhinorrhea	0	1	0
Dyspnea	2	1	1
Upper Respiratory Tract Disorder	7	5	4
SKIN/SUBCUTANEOUS TISSUE
Epidermal and Dermal Conditions
Rash	1	3	2
Pruritis	0	1	1
METABOLISM & NUTRITION
Appetite/General Nutrit. Disorders
Increased appetite	4	3	2
Decreased appetite/Anorexia	1	2	1

The overall pattern and frequency of adverse events during the longer-term trials was similar to those described in Table 1, though several of the most common events were reported by a greater proportion of patients with long-term use (e.g., nausea was reported in 40% of patients treated with Chantix 1 mg twice daily in a one-year study, compared to 8% of placebo-treated patients).

Following is a list of treatment-emergent adverse events reported by patients treated with Chantix during all clinical trials. The listing does not include those events already listed in the previous tables or elsewhere in labeling, those events for which a drug cause was remote, those events which were so general as to be uninformative, and those events reported only once which did not have a substantial probability of being acutely life-threatening.

Blood and Lymphatic System Disorders. Infrequent: anemia, lymphadenopathy. Rare: leukocytosis, splenomegaly, thrombocytopenia.

Cardiac Disorders. Infrequent: angina pectoris, arrhythmia, bradycardia, myocardial infarction, palpitations, tachycardia, ventricular extrasystoles. Rare: acute coronary syndrome, atrial fibrillation, cardiac flutter, cor pulmonale, coronary artery disease.

Ear and Labyrinth Disorders. Infrequent: tinnitus, vertigo. Rare: deafness, Meniere's disease.

Endocrine Disorders. Infrequent: thyroid gland disorders.

Eye Disorders. Infrequent: conjunctivitis, dry eye, eye irritation, eye pain, vision blurred, visual disturbance. Rare: acquired night blindness, blindness transient, cataract subcapsular, ocular vascular disorder, photophobia, vitreous floaters.

Gastrointestinal Disorders. Frequent: diarrhea. Infrequent: dysphagia, enterocolitis, eructation, esophagitis, gastritis, gastrointestinal hemorrhage, mouth ulceration. Rare: gastric ulcer, intestinal obstruction, pancreatitis acute.

General Disorders and Administration Site Conditions. Frequent: chest pain, edema, influenza-like illness. Infrequent: chest discomfort, chills, pyrexia.

Hepatobiliary Disorders. Infrequent: gall bladder disorder.

Investigations. Frequent: liver function test abnormal, weight increased. Infrequent: electrocardiogram abnormal, muscle enzyme increased, urine analysis abnormal.

Metabolism and Nutrition Disorders. Infrequent: diabetes mellitus, hyperlipidemia, hypokalemia. Rare: hypoglycemia.

Musculoskeletal and Connective Tissue Disorders. Frequent: arthralgia, back pain, muscle cramp, musculoskeletal pain, myalgia. Infrequent: arthritis, osteoporosis. Rare: myositis.

Nervous System Disorders. Frequent: disturbance in attention, dizziness, sensory disturbance. Infrequent: amnesia, migraine, parosmia, psychomotor hyperactivity, restless legs syndrome, syncope, tremor. Rare: balance disorder, cerebrovascular accident, convulsion, dysarthria, facial palsy, mental impairment, multiple sclerosis, nystagmus, psychomotor skills impaired, transient ischemic attack, visual field defect.

Psychiatric Disorders. Infrequent: disorientation, dissociation, libido decreased, mood swings, thinking abnormal. Rare: bradyphrenia, euphoric mood.

Renal and Urinary Disorders. Frequent: polyuria. Infrequent: nephrolithiasis, nocturia, urethral syndrome, urine abnormality. Rare: renal failure acute, urinary retention.

Reproductive System and Breast Disorders. Rare: sexual dysfunction. Frequent: menstrual disorder. Infrequent: erectile dysfunction.

Respiratory, Thoracic and Mediastinal Disorders. Frequent: epistaxis, respiratory disorders. Infrequent: asthma. Rare: pleurisy, pulmonary embolism.

Skin and Subcutaneous Tissue Disorders. Frequent: hyperhidrosis. Infrequent: acne, dry skin, eczema, erythema, psoriasis, urticaria. Rare: photosensitivity reaction.

Vascular Disorders. Frequent: hot flush. Infrequent: thrombosis.

Chantix has also been studied in a trial conducted in patients with stable cardiovascular disease, a trial conducted in patients with chronic obstructive pulmonary disease (COPD) and a trial conducted in generally healthy patients (similar to those in the premarketing studies) in which they were allowed to select a quit date between days 8 and 35 of treatment ("alternative quit date instruction trial").

In the trial of patients with stable cardiovascular disease, more types and a greater number of cardiovascular events were reported compared to premarketing studies. Treatment-emergent (on-treatment or 30 days after treatment) cardiovascular events reported with a frequency ≥ 1% in either treatment group in this study were angina pectoris (3.7% and 2.0% for varenicline and placebo, respectively), chest pain (2.5% vs. 2.3%), peripheral edema (2.0% vs. 1.1%), hypertension (1.4% vs. 2.6%), and palpitations (0.6 % vs. 1.1%). Deaths and serious cardiovascular events occurring over the 52 weeks of the study (treatment emergent and non-treatment emergent) were adjudicated by a blinded, independent committee. The following treatment-emergent adjudicated events occurred with a frequency ≥1% in either treatment group: nonfatal MI (1.1% vs. 0.3% for varenicline and placebo, respectively), and hospitalization for angina pectoris (0.6% vs. 1.1%). During non-treatment follow up to 52 weeks, the adjudicated events included need for coronary revascularization (2.0% vs. 0.6%), hospitalization for angina pectoris (1.7% vs. 1.1%), and new diagnosis of peripheral vascular disease (PVD) or admission for a PVD procedure (1.1% vs. 0.6%). Some of the patients requiring coronary revascularization underwent the procedure as part of management of nonfatal MI and hospitalization for angina. Cardiovascular death occurred in 0.3% of patients in the varenicline arm and 0.6% of patients in the placebo arm over the course of the 52-week study.

Adverse events in the trial of patients with COPD and in the alternative quit date instruction trial were quantitatively and qualitatively similar to those observed in premarketing studies.

Postmarketing Experience

The following adverse events have been reported during post-approval use of Chantix. Because these events are reported voluntarily from a population of uncertain size, it is not possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

There have been reports of depression, mania, psychosis, hallucinations, paranoia, delusions, homicidal ideation, aggression, hostility, anxiety, and panic, as well as suicidal ideation, suicide attempt, and completed suicide in patients attempting to quit smoking while taking Chantix [see Boxed Warning, Warnings and Precautions (5.1)]. Smoking cessation with or without treatment is associated with nicotine withdrawal symptoms and the exacerbation of underlying psychiatric illness. Not all patients had known pre-existing psychiatric illness and not all had discontinued smoking.

There have been reports of hypersensitivity reactions, including angioedema [see Warnings and Precautions (5.2)].

There have also been reports of serious skin reactions, including Stevens-Johnson Syndrome and erythema multiforme, in patients taking Chantix [see Warnings and Precautions (5.3)].

There have been reports of myocardial infarction (MI) and cerebrovascular accident (CVA) including ischemic and hemorrhagic events in patients taking Chantix. In the majority of the reported cases, patients had pre-existing cardiovascular disease and/or other risk factors. Although smoking is a risk factor for MI and CVA, based on temporal relationship between medication use and events, a contributory role of varenicline cannot be ruled out.

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Side Effects by Body System - for Healthcare Professionals

Gastrointestinal

Gastrointestinal (GI) side effects have frequently included nausea (7.2% to 40%), flatulence (6% to 9%), constipation (5% to 8.5%), upper abdominal pain (2% to 7.7%), dry mouth (4% to 6%), abdominal pain (5%), dyspepsia (5%), vomiting (1% to 5%), and GI reflux disease (1%). Diarrhea, gingivitis, dysphagia, enterocolitis, eructation, gastritis, GI hemorrhage, mouth ulceration, esophagitis, gastric ulcer, intestinal obstruction, acute pancreatitis, and gall bladder disease have been reported. At least one case of cholecystitis has also been reported, in addition to case of peritonitis and a case of hemorrhoids and rectal prolapse.

The most common side effect associated with varenicline in clinical trials was nausea. Nausea was typically transient and described as mild or moderate in intensity; however, some patients experienced persistent nausea throughout treatment.

Psychiatric

Psychiatric side effects have included insomnia (19%), abnormal dreams (9% to 13%), sleep disorder (2%), and nightmare (2%). Anxiety, depression, emotional disorder, irritability, restlessness, aggression, agitation, disorientation, dissociation, decreased libido, mood swings, abnormal thinking, bradyphrenia, euphoric mood, hallucination, psychotic disorder, suicidal ideation, and erratic behavior have also been reported. Depressed mood, agitation, changes in behavior, and suicide have been reported during postmarketing experience. At least one case of varenicline-induced manic episode has also been reported, in addition to a case of exacerbation of schizophrenia.

A 63-year-old male with stable bipolar disorder experienced a manic episode coincident with varenicline therapy. The patient was admitted to an inpatient psychiatric unit and met criteria for a manic episode. He began exhibiting manic symptoms one week after initiating therapy with varenicline 1 mg twice daily for smoking cessation. Varenicline was stopped upon admission. Within one week of admission, he was euthymic, without manic or psychotic symptoms.

A 42-year-old female with a 17-year history of schizophrenia experienced exacerbation of schizophrenia coincident with varenicline therapy. She had been prescribed varenicline 2 mg for 5-days to help her stop smoking. The patient's mother reported a 5-day psychotic episode that began with increased activity. After she was advised to discontinue varenicline, she had no further exacerbation.

Nervous system

Nervous system side effects have frequently included headaches (10.3% to 19%), dysgeusia (8%), fatigue, malaise, asthenia, somnolence, and lethargy. Attention disturbances, dizziness, sensory disturbance, amnesia, migraine, parosmia, psychomotor hyperactivity, restless legs syndrome, syncope, tremor, balance disorder, cerebrovascular accident, convulsion, dysarthria, facial palsy, mental impairment, multiple sclerosis, nystagmus, impairment of psychomotor skills, transient ischemic attack, visual field defect, and drowsiness have been reported.

Respiratory

Respiratory side effects have frequently included influenza (3.2% to 5.8%), rhinorrhea, dyspnea, and upper respiratory tract disorder. Epistaxis, respiratory disorders, asthma, pleurisy, and pulmonary embolism have also been reported.

Dermatologic

Dermatologic side effects have frequently included rash and pruritus. Hyperhidrosis, acne, dermatitis, dry skin, eczema, erythema, psoriasis, urticaria, and photosensitivity reaction have also been reported.

Metabolic

Metabolic side effects have frequently included increased or decreased appetite and anorexia. Hyperlipidemia, hypokalemia, hyperkalemia, hypoglycemia, and increased weight have also been reported.

Hematologic

Hematologic side effects have included anemia, lymphadenopathy, leukocytosis, thrombocytopenia, and splenomegaly.

Cardiovascular

Cardiovascular side effects have included angina pectoris, arrhythmia, bradycardia, ventricular extrasystoles, myocardial infarction, palpitations, tachycardia, atrial fibrillation, cardiac flutter, coronary artery disease, cor pulmonale, abnormal electrocardiogram, acute coronary syndrome, hypertension, hypotension, peripheral ischemia, and thrombosis.

Endocrine

Endocrine side effects have included thyroid gland disorders and diabetes mellitus. At least one case of pituitary hemorrhage has also been reported.

Ocular

Ocular side effects have included conjunctivitis, dry eye, eye irritation, blurred vision, visual disturbance, eye pain, acquired night blindness, transient blindness, cataract subcapsular, ocular vascular disorder, photophobia, and vitreous floaters.

Hypersensitivity

Hypersensitivity side effects including seasonal allergy (2.6% to 5.9%) have been reported.

Genitourinary

Genitourinary side effects have included abnormal urine analysis, polyuria, nocturia, urine abnormality, urinary retention, menstrual disorder, erectile dysfunction, and sexual dysfunction. At least one case of ovarian hematoma has also been reported.

Musculoskeletal

Musculoskeletal side effects have included arthralgia, back pain, muscle cramp, musculoskeletal pain, myalgia, arthritis, osteoporosis, and myositis.

Renal

Renal side effects have included nephrolithiasis, urethral syndrome, and acute renal failure. At least one case of elevated blood creatinine has also been reported.

Immunologic

Immunologic side effects commonly reported have included nasopharyngitis (35.9% to 51%), bronchitis, sinusitis, fungal infection, and viral infection.

Hepatic

Hepatic side effects including abnormal liver function tests have been reported.

Other

Other side effects have included tinnitus, vertigo, deafness, Meniere's disease, chest pain, influenza-like symptoms, edema, thirst, chest discomfort, chills, pyrexia, increased muscle enzyme, and hot flash. At least one case of feeling abnormal has been reported, in addition to a case of elevated aspartate aminotransferase, two cases of elevated alanine aminotransferase, and one case of elevated blood bilirubin.

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