Metoclopramide-induced normalization of impaired gastric emptying in spinal cord injury

In a partial, two-way crossover study of gastric emptying (GE) in spinal cord injury (SCI), fasted, healthy, unmedicated male volunteers were given a 99mTc-labeled liquid meal on two occasions. Metoclopramide (10 mg) was administered intravenously to each subject before the second evaluation of GE. We used single and multiexponential models with linear and nonlinear least-squares regression techniques to study the time-course of the disappearance of 99mTc from the stomach. The GE pattern in all subjects was most accurately characterized by nonlinear analysis (NONLIN) and consisted of two components, an initial adynamic phase and a phase of rapid emptying. The GE t1/2 of a liquid meal decreased from 106.6 +/- 58.3 min (mean +/- SD) in all SCI subjects (quadriplegic plus paraplegic) prior to treatment to 21.6 +/- 8.2 min after the intravenous administration of metoclopramide (p less than 0.006). Significant correlations between GE t1/2 and injury duration (yr) or level of spinal injury were observed. Impaired gastric emptying in SCI can be pharmacologically modified by metoclopramide to resemble a normal gastric emptying profile. Metoclopramide-altered gastric emptying in SCI may be expected to result in changes in the therapeutic efficacy of orally administered drugs when drug absorption is dependent on gastric motility or emptying efficiency.