Reduction of the gastrointestinal side effects of metrizamide myelography with oral dexamethasone.

A prospective, double-blind study was undertaken to assess the effectiveness of oral dexamethasone premedication in reducing a variety of side effects associated with metrizamide myelography. We also examined the relationship between side effects and needle size, total metrizamide dose, radiographic findings, and personality. Patients were randomly assigned to either a placebo group (44 patients) or a dexamethasone group (38 patients). All patients completed a 24-item symptom checklist before and 24 hr after lumbar myelography. In addition, all patients completed the Minnesota Multiphasic Personality Inventory prior to myelography. Analysis of variance demonstrated a statistically significant decrease in the frequency of gastrointestinal side effects (loss of appetite, nausea, vomiting) in the dexamethasone group. There were no significant differences between the two groups for the other 21 symptoms examined. We concluded that premedication with oral dexamethasone significantly reduces the gastrointestinal side effects associated with metrizamide myelography. This reduction was especially important in older patients.