Interest of pharmacoepidemiology for the study of psychotropic drugs

Drug-induced psychiatric disorders: A pharmacovigilance update

The psychiatric risks associated with drugs are sometimes one of the few restrictions on the use of certain drug classes, such as corticosteroids in patients with a history of severe psychotic episodes associated with this drug class. In this non-exhaustive review, we propose to deal with the most recent issues concerning psychiatric disorders induced by drugs and encountered in doctors' clinical practice. Firstly, we look at depressive disorders and suicide risks, secondly at psychotic and manic disorders and thirdly at anxiety and sleep disorders. While lot of drugs are associated with psychiatric disorders, the confounding by indication represents an important methodological gap since information on the psychiatric profile of patients is not always available. This is particularly the case for serotonin reuptake inhibitors and esketamine used as antidepressants. Recent pharmacovigilance concerns of psychiatric disorders emerged with montelukast, orexin receptor antagonists or cystic fibrosis transmembrane regulator (CFTR) modulators.

Towards personalized pharmacology: Antipsychotics and schizophrenia

Since the discovery of the first antipsychotic in 1952, many antipsychotic drugs have been developed, each with different pharmacokinetic and pharmacodynamic properties. The pharmacological heterogeneity of antipsychotic drugs should allow a personalized drug prescription adapted to the different clinical picture of schizophrenia. Schizophrenia is a chronic disease, during which 3 stages of pharmacological intervention can be identified: the first episode psychotic (FEP), the phase of therapeutic stabilization that can progress to situations of resistance, and the question of long-term prescription. During FEP, the choice of the first antipsychotic treatment seems to be underpinned by its safety profile in relation to the patient for whom it is prescribed, according to the adage start low and go-slow. The therapeutic stabilization phase is based on treatment optimization through a rigorous evaluation of the benefits-harm balance, with the use of tools such as personalized therapeutic drug monitoring and pharmacogenetics. Generally speaking, while some antipsychotic drugs seem to present a more favorable efficacy profile in certain situations, the differences are small, whereas the differences in safety are more important and should be considered in the first line. Individual factors such as the presence of co-morbidities, as well as previously experienced treatments must also be taken into account. Finally, the question of maintaining the prescription of antipsychotic drugs over the long term arises in view of the iatrogenic risk with controversial current data. Overall, the personalized prescription of antipsychotic drugs in schizophrenia remains limited by a lack of data in the literature, justifying the development of clinical studies in this field. But at present, the dogma remains that of primum non nocere.

Enhancing the role played by clinical pharmacists in psychiatric settings to better integrate clinical psychopharmacology into the decision-making process

The importance of clinical psychopharmacological knowledge for modern psychiatric care is both well-established and underdeveloped. Although psychiatric pharmacists are identified as experts in psychopharmacotherapy based on pharmacists' overall expertise in pharmacotherapy, in real-life health settings, such is not necessarily the case. As a matter of fact, (1) pharmacists' real expertise in pharmacotherapy is mainly seen as useful to patients (as part of therapeutic education), (2) pharmacists' practice methods are usually circumscribed to the framework of quality processes (e.g. comprehensive medication management) which are not particularly useful to clinicians who have a greater need for pharmacotherapeutic skills, (3) the difficulties in terms of collaboration between pharmacists and physicians are well-known. We describe here the implementation of an alternative system of pharmacotherapy counselling inspired by case by cases in which the remote expertise of pharmacists in psychopharmacology guided prescribers towards the implementation of recommendations from the literature. This shared decision-making process integrates both the clinical elements provided by the psychiatrist and the pharmacotherapeutic information provided by the clinical psychopharmacist, to promote evidence-based medicine (algorithmic data in recommendations) and tailor-made solutions (drug-drug and drug-disease interactions) for patients. In our experience, the success of such an initiative is likely to promote the development of clinical psychopharmacology in psychiatric settings. Importantly, within this framework, the pharmacovigilance unit and psychopharmacologist are useful resources to guide the decision-making process of the pharmacist-psychiatrist duo.