Calcium is best-known as a supplement to support bone health, but it also has a long history of use to control diarrhea, especially protease inhibitor-related diarrhea, in people with HIV.
Below are a couple of recent Canadian studies that tend to re-affirm the effectiveness of this widely used strategy. See also the NYBC entry on Digestive Maintenance, which includes two types of Calcium supplement.
Turner MJ, Angel JB, Woodend K, Giguère P. The efficacy of calcium carbonate in the treatment of protease inhibitor-induced persistent diarrhea in HIV-infected patients. HIV Clin Trials. 2004 Jan-Feb;5(1):19-24. Pharmacy Department, The Ottawa Hospital, Ontario, Canada.
BACKGROUND: Although some evidence exists to support the practice of using calcium carbonate to treat nelfinavir-induced diarrhea, there is a lack of data supporting the role of calcium in diarrhea induced by other protease inhibitors (PIs). PURPOSE: The objective of this prospective open-label study is to evaluate the efficacy of calcium carbonate in the treatment of PI-induced persistent diarrhea in HIV-infected patients. METHOD: Along with dietary advice, patients were asked to take oral calcium carbonate 500 mg twice daily for 2 weeks. Visual Analog Scale (VAS) and the National Cancer Institute of Canada (NCIC) scale were used to assess the severity of diarrhea. Data were analyzed using paired t tests to test for differences in VAS and NCIC scores between baseline and 14 days. Pearson correlation was used to explore the relationships between change in diarrhea and patient baseline factors. RESULTS: At day 0, the mean VAS +/- standard deviation was 6.6 +/- 2.1 and decreased to 5.3 +/- 1.9 (p=.01) after 14 days. At day 0, the mean NCIC score was 1.9 +/- 0.8 and decreased to 1.2 +/- 0.9 (p=.005) after 14 days. No baseline patient factors predicted change in NCIC or VAS grade. CONCLUSION: Calcium carbonate is associated with a reduction of diarrhea in individuals with diarrhea induced by PI.
Rachlis A, Gill J, Baril JG, LeBlanc RP, Trottier B, MacLeod J, Walmsley S, Van der Vliet W, Belsky G, Burgoyne R. Effectiveness of step-wise intervention plan for managing nelfinavir-associated diarrhea: a pilot study. HIV Clin Trials. 2005 Jul-Aug;6(4):203-12. Sunnybrook and Women’s College Health Sciences Centre, University of Toronto, Ontario, Canada. email@example.com
PURPOSE: Pilot study to evaluate the effectiveness of a step-wise diarrhea management strategy for nelfinavir-associated diarrhea. METHOD: HIV-infected adults (CD4 count > 100 cells/mm3, and no evidence of enteric pathogens) developing symptoms of diarrhea after initiation of nelfinavir for a duration of > or = 1 month were enrolled into this 9-week prospective pilot study. Step-wise interventions, reviewed and adjusted additively at 2-week intervals, included nutritional counseling (+/- lactase and/or psyllium), calcium carbonate, and loperamide. Outcome measure included stool-form consistency, bowel movement frequency, and incidents of associated morbidity (urgency, incontinence) daily. Patient quality of life was also assessed. RESULTS: Eighteen patients completed the study. Mean daily bowel movement frequency decreased by 32%, from 2.98 to 2.03 (p = .005). Mean daily stool form shifted from a rating of 4.24 to 2.37 (p = .0001), representing a shift to firmer stools. Period prevalence of incontinence (28%) and urgency (33%) decreased to 6% each, respectively. Quality of life ratings relating to gastrointestinal disturbance and overall physical/psychosocial function were improved. CONCLUSION: The results of this pilot study demonstrated that a step-wise intensified approach may be successful in managing nelfinavir-associated diarrhea and will need to be validated in a larger scale, randomized controlled trial.