The Effects of Clavulanic Acid on Tobacco Use Disorder

Eligibility Details: Entry criteria: Inclusion Criteria all subjects: 1. Age 18-65 years 2. Right Handed 3. English fluency 4. Smoke > 10 cigarettes/day for a minimum of 2 yrs and have an expired carbon monoxide (CO) concentration of ≥ 10 ppm (to confirm inhalation at screening and scanning); Exclusion Criteria all subjects: 1. Sensitivity or allergy to clavulanic acid/antibiotics. 2. Past head injury or primary neurological disorder associated with MRI abnormalities, including dementia, MCI, brain tumors, epilepsy, Parkinson's disease, or demyelinating diseases. 3. Any physical or intellectual disability affecting completion of assessments 4. Any contraindication to MRI. 5. Any use of psychotropic substances through positive drug screen (such as marijuana or cocaine) or abuse of prescription medications (such as benzodiazepines or opiates) within the last month. Diagnosis of substance use disorder (SUD; other than nicotine) 6. Presence of an untreated illness 7. Current or past psychosis 8. Positive pregnancy test (Urine pregnancy testing at screening and prior to fMRI scan). 9. Use of carbamazepine or nitroglycerin (or any other medication deemed to be hazardous if taken with NAC) within 14 days of study participation