
    recruitment issue
  
['low back pain']
['duloxetine', 'propranolol', 'placebo treatment']

        1. Male or Female patients aged 18 or above.

          2. Chronic Low Back Pain as the primary painful condition. CLBP diagnose based on medical
             history and physical examination, with pain restricted to the low back (T6 or below),
             with or without radiation to the lower limbs but no neurologic signs defined as per
             the Quebec Task Force on Spinal Disorders Class 1 to 3. This pain must be persistent
             in the lower back ≥4 days/week for the past 6 months or longer.

          3. Average pain score of ≥4 at the time of recruitment.

          4. Women of childbearing potential must agree not to become pregnant during the time of
             the study and to use adequate contraception during this time. Adequate contraception
             will be defined as the use of highly effective or double barrier methods. When used
             consistently and correctly, "double barrier" methods of contraception (e.g. male
             condom with diaphragm, male condom with cervical cap) can be used as an effective
             alternative to the highly effective contraception methods such as combined oral
             contraceptives, injectables or intrauterine devices. Both options will be discussed
             during the informed consent process.

          5. Stable drug regimen for 1 month prior to entering the study and throughout the study.
             Patients will not be taken off their current pain medication to participate in the
             study, but they will be asked to keep a stable regimen (not change any doses, add or
             remove other medication) during the study.

          6. Ability to follow study protocol (cognitive and situational).

          7. Ability to write and speak in English and/or French.

          8. Agrees to provide signed and dated informed consent form and biobanking consent form.

          9. Willing to comply with all study procedures, including the biobanking aspect of the
             project and to be available for the duration of the study.

        Exclusion Criteria:

          1. Uncontrolled medical or psychiatric conditions.

          2. History of major depressive disorder, psychotic disorder or schizophrenia, and/or
             manic episodes within the past year.

          3. Pregnancy and/or breast-feeding. Patients who are unsure of their status will also be
             excluded from participating

          4. Pain due to cancer.

          5. Disability compensation or litigation.

          6. Neurologic signs of lumbosacral radiculopathy within the past 6 months: lower
             extremity muscle weakness/sensory loss in a dermatomal distribution, abnormal deep
             tendon reflexes.

          7. Radiographic and/or electrophysiology evidence of radicular compression in the past 6
             months.

          8. Clinical signs of lumbar stenosis within the past 6 months: numbness, weakness, and/or
             discomfort radiating from the spine down to the buttocks and legs while walking or in
             prolonged standing and relieved with sitting or lying.

          9. Clinical signs of back pain that requires an urgent/alternative intervention: new
             onset bowel/bladder incontinence, saddle anaesthesia, foot drop, unexplained weight
             loss, fever.

         10. Radiographic evidence of spinal stenosis, high-grade spondylolisthesis (grade 3 or 4),
             acute spinal fracture, tumour, abscess or acute pathology in the low back/abdominal
             area in the past 6 months.

         11. Low back surgery (lumbosacral spine) within the past 12 months, or history of more
             than 1 low back surgery.

         12. Minimally invasive procedures aimed to reduce pain in the lumbosacral area within the
             past month (Medial Branch Blocks/Ablations, Epidural Steroid Injections, Trigger point
             injections, Sacroiliac Joint Injections, Greater Trochanteric/Acetabulofemoral Joint
             Injections).

         13. Known hypersensitivity to Beta Blockers or SNRIs.

         14. Currently taking SNRIs, Beta Blockers, Opioids at a daily dose superior to 30mg of
             Morphine Oral Equivalent, Tricyclic Antidepressants, Methylene Blue, Linezolid,
             Monoamine Oxidase Inhibitors (such as Selegiline, Isoniazid, Procarbazine),
             Thioridazine, CYP1A2 inhibitors (Fluvoxamine, Verapamil, Cimetidine, Fluoroquinolone
             antibiotics such as Ciprofloxacin).

         15. Active alcoholism within the past 6 months.

         16. Psychoactive recreational drug abuse within the past 6 months including MDMA,
             Ketamine, hallucinogens such as LSD and/or sympathomimetics such as Cocaine.

         17. Patients with asthma, cardiac arrhythmias such as Wolff-Parkinson-White syndrome,
             coronary artery disease, congestive heart failure, renal failure or dialysis, liver
             insufficiency, diabetes mellitus, hyperthyroidism.

         18. Heart rate less than 60 bpm or systolic/diastolic blood pressure less than 105/60 mmHg
             during the initial visit.
      