Cannabidiol for Reducing Cigarette Use

Inclusion Criteria: The investigators will study equal numbers of males and females betweeen 18 - 65 years of age who have Tobacco Use Disorder and express a desire for smoking cessation. Participants will be recruited from the clientele base at Cri-Help Treatment Center in North Hollywood, CA, where the investigators have a long-standing relationship and where the investigators have conducted other research protocols. This study will be conducted at Cri-Help Treatment Center. Participants will not be recruited from the general population for this study because common use of cannabis in the greater Los Angeles area would confound measurements of CBD, interfering with evaluation of the association of plasma level from treatment with efficacy. This problem is avoided in studying participants who are receiving treatment at a facility where cannabis use is not allowed. The investigators will include all racial and ethnic groups. Based on the population of the surrounding communities in the Los Angeles region, the investigators anticipate a racial and ethnic makeup of approximately 26% White, 9% Black/African American, 49% Hispanic/Latino, 14% Asian American, and 2% multi-racial/unknown. These percentages align with our recent studies. Smoking cigarettes and at least moderate nicotine dependence, as indicated by smoking 5 or more cigarettes per day and/or a score of at least 4 on the Fagerström Test for Nicotine Dependence are inclusion criteria. Although vaping is popular and a high proportion of participants who vape also report cigarette smoking (58%), the investigators will exclude participants who vape nicotine. Vaping is not allowed at Cri-Help, Inc. Exclusion Criteria: * Physiological dependence on alcohol or any drug, requiring medical detoxification and/or showing signs of acute withdrawal symptoms from opioids, alcohol or benzodiazepines. * Treatment of Opioid Use Disorder with buprenorphine or methadone to avoid potential drug-drug interactions. CBD interacts with CYP3A. Opioid drugs metabolized by cytochrome P450 (CYP450), and cytochrome P450 isoenzyme CYP3A4 (CYP3A4) in particular, include fentanyl, methadone, oxycodone, and buprenorphine. * Meeting DSM-5 criteria for schizophrenia, Bipolar I disorder, psychotic disorder, having active suicidal ideation, or suicide attempt in the past 12 months. NOTE: Participants with other psychiatric conditions, such as major depression, generalized anxiety, dysthymia, social phobia or specific phobia can enroll if they are clinically stable. * AIDS or current HIV medication treatment with antiviral and/or non-antiviral therapy (due to the interaction of CBD with antiviral therapy). * Clinically significant abnormalities on EKG (such as evidence of arrhythmia or MI). * Clinically significant cardiovascular, hematologic, hepatic, renal, neurological, or endocrine abnormalities \[specific exclusion criteria: AST greater than or equal to 3Xs ULN, Bilirubin greater or equal to 1.5 X ULN, Prothrombin time/International Normalized Ratio (INR) \> 1.5. * Pregnancy and/or lactation. Contraception methods required at time of enrollment, and throughout the duration of the study medication period include abstinence, oral contraceptives, depot contraceptives, condom with spermicide, cervical cap with spermicide, diaphragm with spermicide, intrauterine device, surgical sterilization (e.g. tubal ligation, vasectomy). * Because of evidence that CBD affects ovarian function in rats, women with values outside the reference ranges on a hormonal battery \[estradiol, follicle- stimulating hormone, free thyroxine index, luteinizing hormone, prolactin, total T3 and total T4, thyroid-stimulating hormone\], followed by an abnormal ovarian ultrasound finding will be excluded. * Based on data obtained using Epidiolex® (CBD) oral solution label section 7, "Drug Interactions", the investigators will exclude participants who are taking the following medications: a) strong inducers of CYP3A4 or CYP2C19, which may decrease CBD plasma levels; and b) substrates of UGT1A9, UGT2B7, CYP2B6, CYP2C19 due to the potential of CBD to inhibit enzyme activity.