INTRODUCTION: Lenalidomide is an immunomodulatory drug used for both induction and maintenance in Multiple Myeloma patients. In the pooled multiple myeloma studies, 29.2% of patients reported diarrhea with lenalidomide and dexamethasone. Colesevelam hydrochloride, a drug used primarily for lipid-lowering, has shown efficacy when used for diarrhea in patients receiving lenalidomide in European studies. METHOD: In our retrospective analysis, we have evaluated the response of twenty patients receiving lenalidomide and experiencing chronic diarrhea between October 29, 2013, and August 5, 2014. Patients were prescribed colesevelam hydrochloride, 1875mg orally twice daily. Patients were instructed to dose their lenalidomide and colesevelam separated by at least two hours. The objective is symptomatic improvement in lenalidomide induced diarrhea. RESULTS: Twelve males and eight females on lenalidomide based therapy experiencing chronic diarrhea were prescribed colsevelam. Seventeen patients were receiving single agent lenalidomide and three patients were receiving combination therapies (elotuzumab/lenalidomide/dexamethasone:1 pt, lenalidomide/bortezomib/dexamethasone: 1 pt, and lenalidomide/cyclophosphamide/dexamethasone: 1 pt). Median age of the patients was 60 year (range: 44-77 yrs). Median prior lines of therapy were 1 (range: 1-6). Median time from initiation of lenalidomide to Colesevelam hydrochloride is 44 months (0-64 months). Eighty-five percent of patients have noted improvement and 30% experienced total resolution of symptoms. Median time from initiation of Colesevelam hydrochloride to symptomatic response is 4 weeks (range, 0-17). In one patient response was seen in less than a week. CONCLUSION: Multiple Myeloma patients on lenalidomide therapy with chronic diarrhea noted improvement or total resolution of symptoms with the addition of colesevelam, thus allowing patients to stay on therapy, improving survival as well as quality of life. Disclosures Gleason:Celgene: Consultancy; Novartis: Consultancy. Lonial:Millennium: The Takeda Oncology Company: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Onyx Pharmaceuticals: Consultancy, Research Funding.