Inclusion Criteria:  Adult over 18 years old Diagnosis of fibromyalgia syndrome according to ACR 2016 criteria PCL-5 > 44 suggesting the presence of a comorbid post-traumatic stress disorder Meet the DSM-5 criteria for post-traumatic stress disorder secondary to exposure to a traumatic event according to DSM-5 criteria, both unique or repeated and regardless of the date or location of the traumatic event. Pain relief treatment and/or psychotropic treatment stabilized for a period greater than or equal to two months. Signature of a consent form Patient able to understand and read french  Exclusion Criteria:  Psychotic disorders Unstable bipolar disorder Patients with a systolic blood pressure < 100 mmHg or heart rate < 55 as established during the initial visit Significant anormal ECG Medical contraindication to taking propranolol Adverse reactions or previous intolerances to a beta blocker Current intake of another beta blocker which can not be stopped during the protocol, regardeless the galenic. Current intake of a drug with potential contraindication with the propranolol, according to the summary of product characteristics of the propranolol. Patient under legal protection, under guardianship or under curatorship Patient having suffered a head trauma for less than a year or with clinical symptoms and neurological sequelae Known severe suicide risk (MINI-S and medical exam) Current opioid addiction or alcohol dependence Patients treated for less than 2 months with antidepressants or painkillers Patients unafiliated to a social health care Woman who is pregnant or breast-feeding or whithout efficient contraception