Objective: To determine the effect of C-reactive protein (CRP) status, and infliximab
treatment on the pharmacodynamics and pharmacokinetics of verapamil, a model drug for L-type
calcium channel blocking, in Crohn's disease (CD) patients compared to healthy patients.
Hypotheses:CD patients will have elevated plasma verapamil concentrations, but diminished
dromotropic response to verapamil; the concentration of circulating norepinephrine, used as a
surrogate marker of sympathetic nervous activity, will be similar between the healthy
patients and the CD patients; the sympathetic nervous system of the heart will be similar to
healthy patients; Crohn's disease patients with normal CRP will have higher drug response
compared to high CRP (>3 mg/l) patients; and that infliximab-treated patients will have
higher verapamil response than those with similar symptom profiles who are not infliximab
treated.