Background: Norepinephrine transporter inhibitors that can alter the level of neurotransmitter in the brain are used to treat neurological disorders. However, a number of studies have reported their limited significance as a result of their slow onset of action and moderate efficacy.
Objectives: To determine the effects of norepinephrine reuptake inhibitors (NRIs), reboxetine and atomoxetine on schizophrenia and attention deficit hyperactivity disorder (ADHD).
Material and methods: Relevant articles published between 2000 and 2022 were searched in the MEDLINE, CINAHL (via Ebsco), Web of Science and Scopus databases. Among the various NRIs, studies concerning the 2 potent drugs - reboxetine and atomoxetine - were selected for analysis. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were estimated, along with the exploration of heterogeneity and publication bias, using RevMan software.
Results: A total of 14 eligible studies with a combined sample size of 970 patients were included. Using a random effects model, an OR of 0.55 (0.32-0.94), a Tau2 value of 0.23, a ÷2 value of 12.31, 8 degrees of freedom (df), an I2 of 35%, a Z value of 2.19, and a p-value of 0.03 were recorded for reboxetine. Atomoxetine had an OR of 0.35 (0.13-0.97), a Tau2 value of 0.58, a ÷2 value of 7.31, 4 df, an I2 of 45%, a Z value of 1.53, and a p-value of 0.04. All results were statistically significant with a low risk of publication bias, as was evident from the p-values >0.05 derived from the Egger's test and the Begg's test. These drugs provided comparable changes to control drugs in Hamilton Depression Rating Scale (HAM-D) scores, Positive and Negative Syndrome Scale (PANSS) scores and ADHD ratings. This confirms the efficacy of reboxetine for the treatment of schizophrenia and atomoxetine for the treatment of ADHD.
Conclusion: The present meta-analysis suggests that NRIs are efficacious and therefore they are potential candidate drugs for the treatment of schizophrenia and ADHD.
Keywords: atomoxetine; attention deficit hyperactivity disorder; neurological disorders; reboxetine; schizophrenia.