We investigated the effect of concurrent ingestion of Garcinia kola seed on the pharmacokinetics of quinine. In a randomized crossover study, 24 healthy Nigerian volunteers were assigned into two groups (A and B; n = 12 per group) on the basis of G. kola dose orally ingested. Each subject received 600mg quinine sulphate before and after ingesting 12.5g of G. kola once daily for seven days (Group A) or 12.5g twice daily for six days and once on the seventh day (Group B). Blood samples were collected and analyzed for plasma quinine and its metabolite, (3-hydroxyquinine) using a validated HPLC method. Concurrent administration of quinine with G. kola reduced quinine tmax by 48% (group A), mean Cmax by 19% and 26% in groups A and B, and slight reduction in mean AUC0–∞ of quinine in both groups. 3-hydroxyquinine Cmax also reduced by 29% and 32%; AUC0–∞ by 13% and 9% respectively. The point estimates of the T/R ratio of the geometric means for all Cmax obtained and only the AUC0–∞ at a higher dose of G. kola were outside the 80–125% bioequivalence range. In conclusion, an herb-drug interaction was noted with concurrent quinine and G. kola administration.

Aqueous extract of Hibiscus sabdariffa lowered T better than simvastatin and enhanced the antihyperlipidaemic activity of the drug when co-administered at low doses in an animal model. However, aqueous beverage of Hibiscus sabdariffa caused a significant herb-drug interaction resulting in overall reduction in exposure to simvastatin in humans. Caution should thus be placed on clinical judgement or recommendations based on the animal results. Nevertheless, co-administration of the beverage with simvastatin should be discouraged until more clinical data are available.

HighlightsVaried disposition imparts on the tolerance and safety of quinine, and thus constitutes a major limiting consideration for its dosing in uncomplicated malaria. Utilizing a population approach, the effect of body weight and infection status on disposition parameters of quinine were evaluated in Nigerian subjects.A reversal of infection-induced changes in volume of distribution and clearance after 48 h of chronic quinine administration was noted.It is hypothesized that a downward review of quinine regimen post-48 h of chronic administration, in the event of complete parasitaemia clearance, might be a useful approach in enhancing tolerance and safety.

IntroductionThere is a scarcity of epidemiological data on neurodegenerative diseases (NDs) in East Africa. This meta-analysis provides the regional prevalence of NDs, their contributing factors, and evidence of change over time concerning gender per age or year.MethodsArticles were retrieved from electronic databases following the PRISMA standard.ResultsForty-two studies were reviewed, and 25 were meta-analyzed with a random-effects model. The pool estimate proportion of 15.27%, 95% CI (0.09–0.23) (I2 = 98.25%), (Q = 1,369.15, p < 0.0001) among a population of 15,813 male/female and 1,257 with NDs. Epidemiological characteristics associated with NDs include Dyskinesias prevalence 55.4%, 95% CI (13.5; 90.9), I2 (96%) and subsistence farming prevalence 11.3%, 95% CI (5.8; 20.9), I2 (99%). Publication bias by Egger test was (z = 4.1913, p < 0.0001), while rank correlation test using Kendall's model was (tau = 0.1237, p = 0.3873). Heterogeneity (R2 design = 5.23%, p design < 0.0001; R2 size = 52.163%, p size < 0.001; and R2 period = 48.13, p period < 0.0001. Covariates (R2 design + size + period = 48.41%, p < 0.001).ConclusionThere is a high prevalence of NDs in the East African region, which could impact life expectancy, morbidity, and quality of life. Thus, early screening and regular surveillance could assist in management strategies.