Acute antihypertensive effect of nifedipine on high and low salt diet

To examine the influence of sodium balance in the acute response to nifedipine, we studied 10 untreated essential hypertensive patients aged 29 to 43 years. Blood pressure was recorded with the patients fasting and lying in the supine position, and 10 mg nifedipine was administered sublingually. Blood pressure was recorded again 3 h after nifedipine. Patients were studied after 1 week on both their unrestricted usual diet (NaU 206 +/- 29 mmol/day) and a low salt diet (NaU 66 +/- 8 mmol/day). The maximum hypotensive effect of nifedipine was observed at 90 min. The decrease of blood pressure tended to be greater and longer on high salt than low salt diet. Our results suggest that the acute antihypertensive effect of nifedipine is enhanced by sodium administration.