Introduction Long acting injectable (LAI) antipsychotics are commonly used in the treatment of schizophrenia to improve adherence and clinical outcomes. Concerns have been reported in relation to their non-systemic or injection site adverse effect profile. As such, this study aims to review and evaluate all evidence reporting injection site adverse effects with LAI antipsychotics. Methods An electronic search was systematically conducted through four databases (PubMed, Embase, SCOPUS, Cochrane) in order to identify studies investigating injection-site reactions associated with LAI antipsychotics. Unpublished studies such as conference proceedings and clinical trial registries were also searched. The search was limited to literature published in English without year limits. Results Of a total of 189 citations that were identified from the electronic database search, 12 were selected for inclusion in this review. Various injection site reactions were reported in these studies, including pain, bleeding, and swelling. Overall, the studies reported a low incidence of these injection site reactions. Only a minority of the included articles compared injection site reactions between different LAI antipsychotics. Conclusion Injection site pain was the most commonly reported injection site adverse effect across all articles reviewed. The low incidence of injection site adverse effects associated with LAI antipsychotics indicates that these formulations appear to be well tolerated by patients. More head-to-head trials comparing second generation LAI antipsychotics are needed.

There is no strong evidence on pharmacogenetics role on the quality of INR control after the initiation phase and on the maintenance of stable INR on the long term as measured by the time in therapeutic range (TTR). The benefit of a score such as SAMe-TT 2 R 2 is that it can preemptively guide clinicians on whether to start the patient on warfarin or direct oral anticoagulant. To determine the association between genetic variants in CYP2C9, VKORC1, and CYP4F2 and TTR. To validate SAMe-TT 2 R 2 score predictive ability on the quality of anticoagulation in Qatari patients. This is an observational nested case-control study that was conducted on a cohort of Qatari patients treated with warfarin with previously identified genotype for the CYP2C9, VKORC1, and CYP2F4. The sample size of this cohort was 148 patients. Mean TTR was 62.7 ± 21%. TTR was not significantly different among carriers of the CYP2C9*2 &*3, VKORC1(-1639G>A) or CYP4F2*3 compared to their non-carriers alleles. None of the factors in the SAMe-TT 2 R 2 score had a significant effect on the TTR except for the female gender where TTR was significantly lower in females (n = 89) compared to males (n = 59) (59.6 ± 21% vs. 67.2 ± 20%, p = 0.03). Furthermore, patients with SAMe-TT 2 R 2 score of zero had significantly better TTR compared to those with higher scores (76.5 ± 17% vs. 61.8 ± 21%, p = 0.04). Logistic regression analysis showed that high SAMe-TT 2 R 2 score was the only statistically significant predicting factor of poor INR control (odds ratio (OR) 5.7, 95% confidence interval (CI) 1.1-28.3, p = 0.034). Genetic variants have no contribution to the quality of INR control. SAMe-TT 2 R 2 score was predictive for the poor quality of anticoagulation in a cohort of Qatari patients. Keywords Same-TT 2 R 2 • Pharmacogenetics • Warfarin • Direct oral anticoagulants • Time in therapeutic range Highlights • SAMe-TT 2 R 2 is a tool that can preemptively guide clinicians on whether to start the patient on warfarin or direct oral anticoagulant. • There is no strong evidence on pharmacogenetics role on the quality of INR control and TTR after the initiation phase. • This research shows that genetic variants have no contribution to the quality of INR control. • Our results also indicate that SAMe-TT 2 R 2 score is predictive for the poor quality of anticoagulation in a cohort of Qatari patients.