Reconsolidation Blockade of Intrusive Trauma- and Cocaine-related Memories (Memocycline)

General Inclusion Criteria: Ability to read, understand and provide written informed consent Age between 18 and 60 years To be sufficiently fluent in German Inclusion Criteria for the PTSD group: - Current diagnosis of full PTSD according to the 5th version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), of subthreshold PTSD, as in meeting two to three of the DSM-5 criteria B-E, or of complex PTSD Inclusion Criteria for the CUD group: Current diagnosis of mild, moderate, or severe CUD according to DSM-5 Regular cocaine use in the last 12 months and at least one consumption event in the last 6 months General Exclusion Criteria: Women who are pregnant or breast feeding or intending to become pregnant during the course of the study or within 3 months after Other clinically significant concomitant disease states, e.g., renal failure (i.e., estimated glomerular filtration rate (eGFR; CKD-EPI) lower than 60 ml/min/1.73 m2), hepatic dysfunction (i.e., alanine transaminase (ALT) higher than 90 U/I for women or 110 U/I for men, aspartate aminotransferase (AST) higher than 74 U/I, and/or gamma-glutamyl transferase (γGT) higher than 70 U/I for women or 120 U/I for men), cardiovascular disease, etc. Presence or history of severe neurological disorders, head injuries or systemic/rheumatic disease Diagnosis of schizophrenia, bipolar disorder, or autism spectrum disorder according to DSM-5 Pacemaker, neurostimulator or any other head or heart implants as well as MRI-incompatible metal parts or possibility of metal fragments in the body (MR safety) Claustrophobia (MR safety) Dependence on a hearing aid (MR safety) Inability to follow the procedures of the study, e.g., due to language problems Participation in another study with investigational drugs within the 30 days preceding and during the present study More than three suicide attempts in the past, a suicide attempt within the last 12 months and/or acute suicidality Exclusion Criteria for Healthy Controls: Any current psychiatric diagnosis according to DSM-5 except for mild or moderate substance use disorder (SUD) for nicotine, and mild SUD for alcohol and cannabis Exclusion Criteria for both the PTSD and CUD groups: Allergy to minocycline or to any other ingredient in the named drug Current intake of the following medications interacting with minocycline: acitretin, acetylcystein, aluminiumhydroxid, amitryptiline, any antibiotics, antidiabetic drug such as sulfonylurea, atazanavir, atomoxetine, anticoagulant drugs from the coumarin type, barbiturates, bupropion, carbamazepine, ciclosporin A, isotretinoin, methotrexate, phenytoin, and theophylline Exclusion Criteria for only the PTSD group: Diagnosis of CUD according to DSM-5 (lifetime) Current diagnosis of severe SUD for nicotine, moderate SUD for alcohol and cannabis, and mild SUD for all other substances according to DSM-5 Exclusion Criteria for only the CUD group: Diagnosis of PTSD according to DSM-5 (lifetime) Current diagnosis of severe SUD for alcohol or cannabis, and mild SUD for all other substances (except for nicotine) according to DSM-5