In a double-blind placebo-controlled study, we examined the effect of caffeine pretreatment on the haemodynamic and humoral changes after a standardized breakfast in 15 healthy elderly subjects (mean age 75.4 +/- 6.6 years). After placebo, the preprandial blood pressure did not change and the postprandial blood pressure declined by a maximum of 6.1%. After oral ingestion of 250 mg caffeine, 60 min before breakfast, the preprandial blood pressure increased by 12.5%. Although the decrease of the postprandial blood pressure was not altered, blood pressure remained above its basal value. The increase in plasma noradrenaline after the meal was similar in the placebo and the caffeine tests. Plasma adrenaline decreased after placebo (-19%) but did not change after caffeine. Thus, despite the unchanged decrease of the postprandial blood pressure, the preprandial pressor effect of caffeine prevented the decline of the postprandial blood pressure below its baseline value. The clinical relevance of this finding has still to be determined.