# Abstract

 

## Background We aimed to quantify the glycemic effects of quinine in healthy individuals. 

## Methods We evaluated the glycemic profile in response to 4 h infusion of 500 ml of 0.9% saline versus 5% glucose solution with and without quinine at therapeutic dose (500 mg) in ten healthy volunteers (8 men) aged 28 ± 9 years. The order of the fourth explorations was randomly assigned. During these explorations, we measured blood glucose every 15 min for 4 h and compared the mean and glycemic fluctuations for each test. A resting ECG was performed before and after quinine infusion in each participant. 

## Results The mean glycemic level during the 4-h infusion was 83 ± 5 mg/dl without quinine versus 74 ± 5 ​​mg/dl with quinine (p \< 0.001) using saline solute versus 92 ± 7 mg/dl without quinine versus 82 ± 5 mg/dl with quinine (p \< 0.001) when associated with the glucose solute. In isotonic dirty solute, quinine induces a cumulative glycemic decrease of 17.5% (p = 0.01) characterized by a nadir estimated at −26.5% at the 60th minute (65 ± 23 mg/dl), p \<0.001 followed by a gradual increase until the 4th hour. There were no signs of hypoglycemia or significant prolongation of the QT interval at the ECG. Overall, quinine did not induce a significant change in blood glucose with glucose compared to saline. 

## Conclusion The intravenous infusion of quinine at a therapeutic dose induces a light drop in blood glucose with a significant nadir at the 60th minute in the healthy subject without hypoglycemia. This suggests the need for close monitoring in patients at risk of hypoglycemia such as those with severe malaria especially during the first hour of quinine infusion. # Results Quinine infusions were all well tolerated. No subject reported having symptomatic hypoglycemia or significant cardiotoxicity during or after any test day of the study. 

## Plasma glucose The mean capillary glycemia during 4 h of infusion were 0.83 ± 0.05, 0.92 ± 0.07, 0.74 ± 0.05 and 0.82 ± 0.05 g/l on normal saline, dextrose 5%, normal saline containing quinine and dextrose 5% containing quinine respectively. On the other hand, the matched mean venous glycemia were 0.97 ± 0.02, 0.99 ± 0.35, 0.97 ± 0.06 and 0.93 ± 0.40 g/l, respectively. On comparing the mean capillary glucose, there was a statistically significant difference between mean glucose levels on isotonic saline and those on isotonic dextrose (p \< 0.001). The ratio of the area under curve for saline and saline plus quinine infusions was 89%; thus a decrease in blood sugar of 11% induced by quinine over 4 h. At the 60th min, the maximum glycemic drop was observed; 26.5% for quinine in isotonic saline and 7.6% for quinine in isotonic glucose (p \< 0.001). There was a significant difference (p \< 0.001) between mean values during the 4 h of saline infusion versus saline + quinine infusion as shown in Fig. [1](#). <figure> <p><img src="" /></p> <figcaption>Mean plasma glucose concentrations during a 4 h infusion of 500 ml of saline in healthy volunteers, with a subsequent 4 h infusion of saline with quinine 8 mg/kg body weight</figcaption> </figure> Concerning the 12 lead ECG done before and after the administration of quinine in either isotonic saline or isotonic glucose, lengthening of the QT interval was not statistically significant (p > 0.05). None of the healthy volunteers presented symptoms or signs of hypoglycemia during the experimental phase.


Extracted trial result:
Outcome: QT interval (continuous)
Intervention: Saline + Quinine infusion
Comparator: Saline without Quinine infusion
Intervention group size: 10
Comparator group size: 10
Notes: No numerical values are given.