(iv) Efficacy of high dose diazepam (during infusion of chloroquine)
In contrast to trial (ii), an infusion of chloroquine for 30 minutes did not cause significant changes in all haemodynamic or ECG parameters. Chloroquine did not reduce mean BP, heart rate or increase the QTc interval significantly in those randomised to diazepam; and did not increase the QRS interval in either group. Following intervention, heart rate was significantly increased in the diazepam group; other parameters were no different between treatment groups (Table 3).
The whole blood chloroquine concentration in these rats was 12.2 ± 0.8 µM after 25 minutes of infusion (1 mg kg-1min-1), 14.3 ± 0.9 µM after 45 minutes, and 16.3 ± 1.1 µM after 60 minutes.