What variable must be known to calculate an appropriate loading dose?

In the management of a cardiac arrhythmia, lidocaine is to be administered by way of an IV loading dose. What variable must be known to calculate an appropriate loading dose?

A. renal clearance
B. bioavailability
C. volume of distribution
D. lag time
E. time to steady-state

Answer: E. Cholestyramine and colestipol are resins that sequester bile
acids in the gut, preventing their reabsorption. This leads to release of their
feedback inhibition of 7-alpha hydroxylase and the diversion of cholesterol
toward new synthesis of bile acids. Increase in high-affinity LDL receptors on
hepatocyte membranes decreases plasma LDL. These drugs have a small but
significant effect to increase plasma HDL rather than decrease it, but their
ability to increase TGs precludes their clinical use in the management of
hypertriglyceridemias.