Guanfacine for Alcohol Use Disorder (AUD)

Inclusion Criteria: * be assigned as a biological male or female at birth and identify as such * meet current Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM V) criteria for moderate to severe AUD * be ≥18 years old and have a body mass index (BMI) of 18-35 * express a desire to quit alcohol as determined by the Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES) * demonstrate a positive urine for alcohol on admission to study procedures * be able to provide informed verbal and written consent * be able to read English and complete study evaluations * be in good health as verified by the intake 1 physical examination Exclusion Criteria: * meet criteria for moderate to severe Substance Use Disorder (SUD), excluding alcohol and nicotine * have a positive screen for substances of abuse, excluding alcohol, nicotine, * being psychotic or otherwise severely psychiatrically disabled (including suicidal, homicidal, current mania) * meet criteria for physiological dependence on alcohol requiring medical detoxification * regular use of medications in the last 6 months that, in the opinion of the site physician may be contraindicated with GXR and be potentially harmful to the participant * be pregnant or breast feeding * be using monophasic contraceptives * have cardiovascular disease including high blood pressure, * be hypotensive with sitting blood pressure below 100/50 mmHG * have bradycardia with a sitting heart rate (HR) of \<60 bpm * show EKG evidence of any clinically significant conduction abnormalities, including a Bazett's corrected QT interval (QTc) \>470 msec for women and QTc\>450 msec for men.