Lessons from pharmacogenetics and metoclopramide: toward the right dose of the right drug for the right patient

Ondansetron: recommended antiemetics for patients with acute pancreatitis? a population-based study

Objective: Ondansetron administration is a common antemetic of acute pancreatitis therapy in the intensive care unit (ICU), but its actual association with patients' outcomes has not been confirmed. The study is aimed to determine whether the multiple outcomes of ICU patients with acute pancreatitis could benefit from ondansetron. Methods: 1,030 acute pancreatitis patients diagnosed in 2008-2019 were extracted from the Medical Information Mart for Intensive Care (MIMIC)-IV database as our study cohort. The primary outcome we considered is the 90-day prognosis, and secondary outcomes included in-hospital survival and overall prognosis. Results: In MIMIC-IV, 663 acute pancreatitis patients received ondansetron administration (OND group) during their hospitalization, while 367 patients did not (non-OND group). Patients in the OND group presented better in-hospital, 90-day, and overall survival curves than the non-OND group (log-rank test: in-hospital: p < 0.001, 90-day: p = 0.002, overall: p = 0.009). After including covariates, ondansetron was associated with better survival in patients with multiple outcomes (in-hospital: HR = 0.50, 90-day: HR = 0.63, overall: HR = 0.66), and the optimal dose inflection points were 7.8 mg, 4.9 mg, and 4.6 mg, respectively. The survival benefit of ondansetron was unique and stable in the multivariate analyses after consideration of metoclopramide, diphenhydramine, and prochlorperazine, which may also be used as antiemetics. Conclusion: In ICU acute pancreatitis patients, ondansetron administration was associated with better 90-day outcomes, while results were similar in terms of in-hospital and overall outcomes, and the recommended minimum total dose might be suggested to be 4-8 mg.

Tardive Dyskinesia and Dopamine Oxidation, Cumulative Effects

It is likely that tardive dyskinsesia is caused by the oxidation of dopamine in dopaminergic neurons. This oxidation produces oxygen radicals that damage neurons. Damage accumulates until tardive dyskinesia occurs. The use of dopamine D2 receptor inhibitors should be limited to the lowest doses for the shortest duration possible.

Genetics and pharmacogenetics of aminergic transmitter pathways in functional gastrointestinal disorders

Functional gastrointestinal disorders (FGIDs) are highly prevalent syndromes, without evident underlying organic causes. Their pathogenesis is multifactorial in nature, with a combination of environmental and genetic factors contributing to their clinical manifestations, for which most of current treatments are not satisfactory. It is acknowledged that amine mediators (noradrenaline, dopamine and serotonin) play pivotal regulatory actions on gut functions and visceral sensation. In addition, drugs of therapeutic interest for FGIDs act on these transmitter pathways. The present article reviews current knowledge on the impact of genetics and pharmacogenetics of aminergic pathways on FGID pathophysiology, clinical presentations, symptom severity and medical management, in an attempt of highlighting the most relevant evidence and point out issues that should be addressed in future investigations.

The ghrelin agonist RM-131 accelerates gastric emptying of solids and reduces symptoms in patients with type 1 diabetes mellitus

BACKGROUND & AIMS

RM-131, a synthetic ghrelin agonist, greatly accelerates gastric emptying of solids in patients with type 2 diabetes and delayed gastric emptying (DGE). We investigated the safety and effects of a single dose of RM-131 on gastric emptying and upper gastrointestinal (GI) symptoms in patients with type 1 diabetes and previously documented DGE.

METHODS

In a double-blind cross-over study, 10 patients with type 1 diabetes (age, 45.7 ± 4.4 y; body mass index, 24.1 ± 1.1 kg/m(2)) and previously documented DGE were assigned in random order to receive a single dose of RM-131 (100 μg, subcutaneously) or placebo. Thirty minutes later, they ate a radiolabeled solid-liquid meal containing EggBeaters (ConAgra Foods, Omaha, NE), and then underwent 4 hours of gastric emptying and 6 hours of colonic filling analyses by scintigraphy. Upper GI symptoms were assessed using a daily diary, gastroparesis cardinal symptom index (total GCSI-DD) and a combination of nausea, vomiting, fullness, and pain (NVFP) scores (each rated on a 0-5 scale).

RESULTS

At screening, participants' mean level of hemoglobin A1c was 9.1% ± 0.5%; their total GCSI-DD score was 1.66 ± 0.38 (median, 1.71), and their total NVFP score was 1.73 ± 0.39 (median, 1.9). The t1/2 of solid gastric emptying was 84.9 ± 31.6 minutes when subjects were given RM-131 and 118.7 ± 26.7 when they were given a placebo. The median difference (Δ)was 33.9 minutes (interquartile range [IQR] -12, -49), or -54.7% (IQR, -21%,-110%). RM-131 decreased gastric retention of solids at 1 hour (P = .005) and 2 hours (P = .019). Numeric differences in t1/2 for gastric emptying of liquids, solid gastric emptying lag time, and colonic filling at 6 hours were not significant. Total GCSI-DD scores were 0.79 on placebo (IQR, 0.75, 2.08) and 0.17 on RM-131 (IQR, 0.00, 0.67; P = .026); NVFP scores were lower on RM-131 (P = .041). There were no significant adverse effects.

CONCLUSIONS

RM-131 significantly accelerates gastric emptying of solids and reduces upper GI symptoms in patients with type 1 diabetes and documented DGE.