Transition From Acute to Chronic Back Pain : Effect of L-dopa,Gender,and Associated Brain Plasticity

Inclusion Criteria: * Age ≥ 18 years * New onset subacute or acute back pain (\< 6 months' duration, no back pain for 3 months before the new onset) * Signs and symptoms: positive straight leg raising test with dermatomal radiation and/or myotomal weakness and/or reflex asymmetry, pain must radiate into buttock or below * Average reported pain intensity from App greater than 4/10 during the first week * MUST be able to undergo MRI procedures (no pacemaker, any metal implants) Exclusion Criteria: * Previous (distinct) episodes of back pain onset (more than 3 distinct episodes of back pain lasting for a total of more than 4 weeks) in the previous year; * Evidence of acute vertebral fracture; * Low back pain associated with any systemic signs or symptoms, e.g., fever, chills; * Symptoms of neuropathy due to diabetes Type I or Type II; * Chronic neurologic conditions, including Parkinson's disease, Alzheimer's disease, and other conditions associated with dementia; * Significant other medical diseases such as congestive heart failure, coronary or peripheral vascular disease, chronic obstructive lung disease, or malignancy; * History of glaucoma or narrow angle glaucoma; * Presence of undiagnosed skin lesions or history of melanoma; * Presence of severe cardiovascular or pulmonary disease, bronchial asthma, renal, hepatic or endocrine disease; * History of myocardial infarction with residual cardiac arrhythmia; * History of gastrointestinal bleeding or peptic ulcer; * Diagnosis of current depression (assessed via BDI, total \> 28 are excluded) or psychiatric disorder requiring treatment, or such a diagnosis in the previous 6 months; * Use of therapeutic doses of antidepressant medications (i.e., tricyclic antidepressants, SSRIs, SNRIs; low doses used only in the evening for sleep will be allowed if dose is not changed; * Current use of recreational drugs or recent history of alcohol abuse (pattern of drinking having social, financial or physical consequences) or drug abuse (urine screening); * Current use of cannabinoids (4 participants tested positive; 3 completed the study, in these blood test at the end of the study confirmed cannabinoid use; excluding these subjects does not importantly alter results, see below); * High dose opioid prophylaxis, defined as \> 50mg morphine equivalent/day; * Use of MAOIs, currently or within the past 2 weeks; * Prior use of levodopa; * Use of any of the following drugs: bromocryptine, linezolid, metoclopramide, phenothiazines…