Inclusion Criteria:  Male or female Veteran of US military; signed informed consent Criterion A Index Trauma(s) resulting in PTSD occurred during adulthood prior to stroke PTSD defined by MINI International Neuropsychiatric Inventory (MINI) for DSM-5 CAPS-5 past week total score =27 at baseline visit Willing to refrain from antipsychotics, mood stabilizers, stimulants, and any formulation of MPH First-ever symptomatic ischemic stroke radiologically verified, occurring within past 1-12 months Females of child-bearing potential (i.e. not postmenopausal or surgically sterile) must be using a medically acceptable method of birth control and should not be pregnant nor have plans for pregnancy or breastfeeding during the study  Exclusion Criteria:  Moderate to severe cognitive impairment (Montreal Cognitive Assessment score <16/30) Poor pre-stroke baseline function of a modified Rankin score >2 Presence of any standard MRI contraindications Current diagnosis of DSM-5-defined bipolar disorder I, schizophrenia, schizoaffective disorder, obsessive-compulsive disorder, or major depressive disorder with psychotic features (MINI)  Diagnosis of moderate or severe substance use disorder (except for caffeine and nicotine) during the preceding 3 months  Patients who utilize alcohol or cannabis but do not meet criteria for moderate or severe disorder are permitted at the discretion of the investigator Participants must agree to abstain from illicit drugs during the study Increased risk of suicide that necessitates inpatient treatment or warrants additional therapy excluded by the protocol; and/or intensity of suicidal ideation (Type 4 or Type 5) or any suicidal behavior in the past 3 months on Columbia Suicide Severity Rating Scale (C-SSRS) Use of any investigational drug, MPH formulation, antipsychotics, mood stabilizers, monoamine oxidase inhibitors, stimulants or any medication known to be a potent (strong) cytochrome P450 subtype 3A4 inhibitor within 2 weeks of baseline  Treatment with evidence-based trauma-focused therapy for PTSD within two weeks of baseline (if participant is receiving therapy, he/she must complete treatment prior to entering study)  Supportive psychotherapy in process at time of Screening may be continued during the study.  History of moderate or severe TBI as defined by the Ohio State University TBI Identification Method  Based on investigator's clinical judgment, history of mild TBI is not excluded Any clinically significant, uncontrolled, or medical/surgical condition or laboratory abnormality that would contraindicate use of MPH (see Human Subjects section) Severe allergic reaction, bronchospasm, or hypersensitivity to any MPH formulation. Litigating for compensation for a psychiatric disorder. Veterans who are in the process of applying for or receiving VA service-connected disability are eligible Current enrollment in another intervention trial for PTSD or stroke Persons imprisoned, diagnosed with terminal illness, or require surrogate for consent