Impact of bariatric surgery on cytochrome P 450 enzyme activity.

Bariatric surgeries are becoming more prevalent as obesity rates continue to rise. Being that it is an effective weight-loss procedure, it can induce significant anatomical, physiological, and metabolic alterations, which affect the pharmacokinetics of various medications. Cytochrome (CYP) P450 is a group of enzymes that are primarily responsible for metabolizing most medications. Bariatric surgery may affect CYP activity and consequently alter metabolism of various medications, and the resulting weight loss may influence the metabolism of various drugs. This study investigates the impact of bariatric surgery on which CYP enzymes are affected and their effects medications. Authors of this study did an extensive literature review and research in databases including PubMed and EMBASE. The evidence was gathered for medication efficacy influenced by enzyme fluctuations to advocate for further studies for patients that undergo bariatric surgery. The search was limited to English-language results and is deemed up to date as of September 2023. There are numerous studies that indicated alterations of the CYP enzyme activity, which affects the pharmacokinetics of medications used to treat acute and chronic conditions after bariatric surgery. There are various mechanisms involved in CYP enzyme activity leading to fluctuations and the clearance of medications and subsequently compromising the efficacy and safety of these agents. It is imperative to conduct more prospective randomized control studies with longer duration to guide clinicians on how to manage medications with various CYP activity for patients' post-bariatric surgery.

Effects of bariatric surgery on drug pharmacokinetics-Preclinical studies.

With the rising worldwide obesity rates, bariatric surgeries are increasing. Although the surgery offers an effective treatment option for weight loss, the procedure causes dramatic physiological and metabolic changes. Animal models in rodents provide a valuable tool for studying the systemic effects of the surgery. Since the surgery may significantly influence the pharmacokinetic properties of medications, animal studies should provide essential insight into mechanisms underlying changes in how the body handles the drug. This review summarizes research work in rodents regarding the impact of standard bariatric procedures on pharmacokinetics. A qualitative literature search was conducted via PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), and EMBASE. Studies that examined bariatric surgery's effects on drug pharmacokinetics in rodent models were included. Clinical studies and studies not involving drug interventions were excluded. A total of 15 studies were identified and assessed in this review. These studies demonstrate the possible impact of bariatric surgery on drug absorption, distribution, metabolism, excretion, and potential mechanisms. Pharmacokinetic changes exhibited in the limited pre-clinical studies highlight a need for further investigation to fully understand the impact and mechanism of bariatric surgery on drug responses.

Assessing Outcomes Between Risperidone Microspheres and Paliperidone Palmitate Long-Acting Injectable Antipsychotics Among Veterans.

BACKGROUND: Long-acting injectable antipsychotics (LAIAs) are integral for managing schizophrenia, schizoaffective disorder, and bipolar I disorder among veterans. Studies comparing LAIAs, such as risperidone microspheres and paliperidone palmitate, are limited. The primary objective of our study was to compare the number of psychiatric hospitalizations among veterans initiated on risperidone microspheres and those taking paliperidone palmitate pre- and post-LAIA initiation. METHODS: We included veterans who had received ≥ 2 injections of risperidone microspheres or paliperidone palmitate between January 1, 2016 and December 31, 2018. Nonadherence was defined as missing an injection by > 3 days for risperidone microspheres and > 7 days for paliperidone palmitate. Pre-LAIA and post-LAIA hospitalizations and rehospitalizations were assessed using a pre-post design with equivalent periods. Descriptive statistics were used for demographics and diagnoses. Nonparametric tests were used to analyze primary and secondary outcomes. RESULTS: The study included 97 veterans; 44 took risperidone microspheres and 53 received paliperidone palmitate. Participants' average mean (SD) age was 46 (13.8) years, 92% were male, and 94% were diagnosed with schizophrenia or schizoaffective disorder. Veterans administered risperidone microspheres had fewer mean (SD) post-LAIA hospitalizations (0.4 [1.0] vs 0.9 [1.5]; P = .02), were less likely to be rehospitalized (22.7% vs 47.2%; P = .013) and had a shorter mean (SD) treatment duration (41.6 [40.2] vs 58.2 [45.7] weeks; P = .04) compared with paliperidone palmitate. CONCLUSION: Veterans receiving risperidone microspheres had fewer posttreatment psychiatric hospitalizations and were less likely to be rehospitalized.