Smoking Cessation Trial in Recurrent Acute Pancreatitis and Chronic Pancreatitis

Inclusion Criteria * Provision of signed and dated informed consent form * Stated willingness to comply with all study procedures and availability for the duration of the study * Male or female, aged 18 or older * Diagnosed with either recurrent acute pancreatitis or chronic pancreatitis as defined by the American Pancreatic Association: o Chronic Pancreatitis (any of the following): i. Moderate/marked pancreas imaging morphology (i.e. ductal and parenchymal abnormalities ii. Pancreatic calcifications iii. Histologic confirmation o Recurrent Acute Pancreatitis: i. Two or more documented attacks of acute pancreatitis, separated by 3 months from one another, defined by at least 2 of the following 3: 1. amylase or lipase values, or both, that are greater than 3 times the upper limit of normal values 2. characteristic cross-sectional imaging 3. typically upper abdominal pain according to the revised Atlanta classification * Currently smoking ≥ 5 cigarettes/day * Explicitly express a desire to quit within 30 days * Ability to take oral medication and be willing to adhere to the study intervention regimen * Willing and able to comply with trial protocol and follow-up Exclusion Criteria * Age \< 18 years * Ongoing acute pancreatitis or prior episode of pancreatitis in previous 30 days * No desire to quit smoking * Currently undergoing smoking cessation intervention (i.e. nicotine replacement therapy, varenicline, counseling, bupropion). * Known allergic reactions to varenicline or bupropion SR * History of seizures * History of an eating disorder (anorexia or bulimia) * Closed head trauma with any loss of consciousness or amnesia in the last 5 year * Ever history of closed head trauma with \> 30 minutes of loss of consciousness or amnesia or resulting in skull fracture or subdural hematoma/brain contusion * Ever history of alcohol withdrawal * Ever history of chronic kidney disease (creatine clearance \< 30 mL/minute) * Liver impairment (i.e. history of cirrhosis) with aminotransferase elevation ≥ 2 times the upper limit of normal and/or alkaline phosphatase elevation ≥ 2 times the upper limit of normal. * History of bipolar disorder or psychosis * Ongoing or recent use (prior 14 days) of any monoamine oxidase inhibitors (isocarboxazid, phenelzine, tranylcypromine, selegiline). * Regular use of potent CYP2B6 inhibitors (i.e. clopidogrel, ticlopidine) * Regular use of CYP2D6 substrates with narrow therapeutic indices (e.g. flecainide, propafenone, tricyclic antidepressants such as nortriptyline, thioridazine, vinblastine) * History of acute angle closure glaucoma * Meet criteria for depression as assessed by the Center for Epidemiologic Studies - Depression (CES-D) with a score of 16 or higher. * Psychiatric hospitalization within 1 year of screening * Participants who have a score of 3 or higher on the Columbus-Suicide Severity Rating Scale (C-SSRS) at enrollment or during any of the study assessments will be excluded * Unable to provide consent for self Incarcerated * Pregnant females. All female patients of childbearing potential must have a negative pregnancy test and must agree to use highly effective (failure rate \<1%) contraception during participation in the study.