Nifedipine gastrointestinal effects

Polonia J, Boaventura I, Gama G, Camoes I, Bernardo F, Andrade P, Nunes JP, Brand o F, Cerqueira-Gomes M. Influence of non-steroidal anti-inflammatory drugs on renal function and 24 h ambulatory blood pressure-reducii effects of enalapril and nifedipine gastrointestinal therapeutic system in hypertensive patients. JHypertens (1995) 13, 925-31. 

Because of effects on smooth muscle, the calcium channel blockers (particularly verapamil (96) but also diltiazem) can cause constipation. This may be due to colonic motor activity inhibition (97). Gastroesophageal reflux can also occur, and the calcium channel blockers should be avoided in patients with symptoms suggestive of reflux esophagitis (98). Calcium channel blockers (verapamil, diltiazem, and nifedipine) can also be associated with an increased incidence of gastrointestinal bleeding, as reported in a prospective cohort study in 1636 older hypertensives, with a relative risk of 1.86 (95% Cl = 1.22, 2.82) compared with beta-blockers (7). However, this finding was not confirmed in other retrospective studies (13,99,100). 

Lavy A. Corrosive effect of nifedipine in the upper gastrointestinal tract. Diagn Ther Endosc 2000 6 39-41. 

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