Combined Antidepressant and Behavioural Intervention

A body of evidence from both animal and human research suggests that antidepressant drugs may induce early changes in emotional processing that interact with environmental factors to produce a later change in mood. This experimental medicine study will examine the effect of citalopram on emotional cognition under different environmental conditions (as manipulated by the presence or absence of behavioural activation training). Participants will be administered either citalopram or placebo over the course of two weeks. Citalopram will be taken either alone or in combination with behavioural activation training.

Inclusion Criteria:Aged 18-65 years inclusiveResident in the UK for the duration of the studyFluent in EnglishNormal or corrected-to-normal visionExperiencing subjective low mood (score of 10 or above on the BDI-II)Experiencing low activity levels (self-reported)Willing and able to give informed consent for participation in the researchAccess to a computer or laptop with a functioning keyboard and a reliable internet connectionExclusion Criteria:Antidepressant treatment or medication prescribed to treat depression/low mood, currently or in the last six monthsCurrent psychological therapy of any kindCurrent or past probable diagnosis of psychosis, bipolar disorder, OCD, PTSD, substance abuse disorder or any eating disorder, as indicated by the SCID-5Current or past diagnosis of any personality disorder (e.g. borderline personality disorder) according to self-reportJudged to be at clinical high risk of suicidePast suicide attemptCurrent or past hospitalisation for mental health reasons1st degree relative with diagnosis of bipolar disorderDiagnosis of a developmental disorder (e.g. ASD, ADHD, Tourette's syndrome, severe learning disability) according to self-report; this excludes cases of mild dyslexia or dyscalculia where in the opinion of the study team such difficulties would not interfere with the performance of the tasks required in this studyDiagnosis of a neurological disorder (e.g. epilepsy, MS) according to self-reportScore of >30 on the BDI-IICurrent use of medication that might interact with the effects of citalopram (except for the contraceptive pill)Known contraindication to citalopram including: past allergic reaction to citalopram or any other medicines, diagnosis of a cardiovascular condition, glaucoma, type 1 or type 2 diabetes, diagnosis of epilepsy, undergoing electroconvulsive treatment (ECT), or current use of any other medication that is associated with prolonged QT-intervalAny other current or past medical conditions which in the opinion of the study medic may interfere with the safety of the participant or the scientific integrity of the studyHeavy use of cigarettes (smoke > 20 cigarettes per day)Heavy use of caffeine (drink > 4 250ml cups/cans of coffee/energy drinks per day)Severely underweight or overweight in a manner that renders them unsuitable for the study in the opinion of the study medicLactose intolerance (due to the study involving administration of a lactose placebo tablet)Pregnancy (as determined by urine pregnancy test taken during the Part 2 screening visit), breast feeding or plans to become pregnantParticipation in an ETB study in the past 6 monthsParticipation in another drug study in the past 3 months