Background: Chemotherapy and targeted therapies are associated with GI toxicities including diarrhea that affects 50% to 80% of patients. Severe complications include dehydration, malnutrition, fatigue, renal insufficiency, and systemic infection. There are no specific prevention strategies, and treatment options are limited. Dose reduction or interruption of anti-cancer medications may lead to decreased efficacy. This survey was conducted to assess current toxicity management patterns and gaps for cancer therapy-associated diarrhea. Methods: An online survey (MedSurvey) with 6 eligibility & 15 practice questions was conducted (April 27 to 30, 2021). Fifty (50) practicing oncologists completed the survey. Results: Among the 50 oncologists,82% have been practicing ≥ 11 years with 24% from an academic setting and 76% from a community setting. They (percent of respondents) prescribed the following anti-cancer medications more than 10 times per week: cytotoxic chemotherapy (86%), targeted agents (78%), and immuno-oncology therapies (80%). Prevention of chemotherapy-induced diarrhea (CID) with Imodium (loperamide) and Lomotil (diphenoxylate and atropine) were commonly administered (10% always, 60% sometimes) as prophylactic treatment prior to the start of chemotherapy. The majority (60%) would prophylactically use a novel agent for a patient with previous CID, and 38% would use this agent for selected anti-cancer therapies. Many oncologists (5% always, 60% sometimes) start chemotherapy at a lower dose and titrate up to prevent CID. Similar treatment patterns were observed for targeted therapy induced diarrhea (TTID). For Grade 1 CID (multiple choices allowed), 18% used observation only for management, whereas 72% prescribed Imodium, and 22% used Lomotil. For Grade 1 TTID (multiple choices allowed), 26% used observation only, 58% prescribed Imodium, and 26% used Lomotil. Dose reduction was implemented 10% and 6% of the time for CID and TTID, respectively. For Grade 2 CID (multiple choices allowed) 4% used observation only, most started either Imodium (82%) or Lomotil (72%), and 34% considered dose reduction as a treatment strategy. For Imodium or Lomotil non-responders, 50% would dose reduce, and 44% would use an alternate anti-diarrheal treatment (e.g., octreotide). TTID had similar treatment patterns. For immune-oncology agents (e.g., ipilimumab, nivolumab, pembrolizumab) 40% suggested induced GI toxicities (e.g., diarrhea/colitis) require an innovation for managing toxicity. Conclusions: Treating cancer therapy-associated diarrhea continues to be a significant challenge with Grade 2/3 often requiring a therapeutic dose reduction or interruption that may impact the efficacy of cancer treatment. Effective management (prevention and treatment) for GI toxicity remains an unmet need for many patients.