H2 blockers, used to treat gastrointestinal ulcers and/or reduce stomach acid, may improve survival among people with cancer, especially after colorectal cancer resection.

Are you a health professional?

This section does not replicate the other information on this topic but provides additional details or context most relevant to professionals.

Modes of action

Modes of anticancer action of cimetidine are described in several reviews.

  • Mechanisms of antitumor action of cimetidine include its ability to interfere with tumor cell adhesion, angiogenesis and proliferation; its effect on the immune system; and inhibition of postoperative immunosuppression.1Kubecova M, Kolostova K, Pinterova D, Kacprzak G, Bobek V. Cimetidine: an anticancer drug? European Journal of Pharmaceutical Sciences. 2011 Apr 18;42(5):439-44.
  • Cimetidine affects the suppressive function of Treg cells by destabilizing their Foxp3 expression.2Zhang Y, Chen Z et al. Cimetidine down-regulates stability of Foxp3 protein via Stub1 in Treg cells. Human Vaccines & Immunotherapeutics. 2016 Oct 2;12(10):2512-2518.
  • Clinical and preclinical studies have shown antitumor and anticancer properties of cimetidine. These attributes are mediated by inhibition of tumor cell adhesion, antiangiogenesis and activation of immune system.3Kubecova M, Kolostova K, Pinterova D, Kacprzak G, Bobek V. Cimetidine: an anticancer drug? European Journal of Pharmaceutical Sciences. 2011 Apr18;42(5):439-44.
  • Cimetidine, but not ranitidine or famotidine, induced the production of an antitumor cytokine, interleukin (IL)-18, by human monocytes and dendritic cells.4Takahashi HK, Watanabe T et al. Cimetidine induces interleukin-18 production through H2-agonist activity in monocytes. Molecular Pharmacology. 2006 Aug;70(2):450-3. 
  • There is some evidence for cimetidine’s immunological mechanisms and for effects on E-selectin mediated adhesion.5Eaton D, Hawkins RE. Cimetidine in colorectal cancer–are the effects immunological or adhesion-mediated? British Journal of Cancer. 2002;86(2):159–160.

Preclinical evidence

Notable preclinical evidence is presented here; clinical evidence is summarized in How can H2 blockers help you? What the research says ›

Improving treatment outcomes

Anticancer activity in cholangiocarcinoma cells6Dana P, Vaeteewoottacharn K et al. Repurposing cimetidine for cholangiocarcinoma: antitumor effects in vitro and in vivo. Oncology Letters. 2017 Mar;13(3):1432-1436.

Anticancer activity in salivary gland cancer cells treated with cimetidine7Fukuda M, Tanaka S, Suzuki S, Kusama K, Kaneko T, Sakashita H. Cimetidine induces apoptosis of human salivary gland tumor cells. Oncology Reports. 2007 Mar;17(3):673-8.

Cimetidine enhanced IFN alpha inhibition of clonal growth of leukemic granulocyte-macrophage colony-forming units from chronic myeloid leukemia patients.8Douer D, Kneller A et al. Effect of alpha interferon on growth of leukemic and normal hematopoietic progenitors. Synergism with H2 histamine receptor antagonists. Experimental Hematology. 1989 Jun;17(5):443-8.

Managing side effects

Cimetidine protected mice against cisplatin ototoxicity and nephrotoxicity.9Ciarimboli G. Membrane transporters as mediators of cisplatin side-effects. Anticancer Research. 2014 Jan;34(1):547-50.

Helpful link for professionals

Cancer Strategies Journal: Clinical Pearls, Summer 2013 ›

See “Cimetidine”

Keep reading about H2 blockers


Nancy Hepp, MS

Lead Researcher
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Ms. Hepp is a researcher and communicator who has been writing and editing educational content on varied health topics for more than 20 years. She serves as lead researcher and writer for CancerChoices and also served as the first program manager. Her graduate work in research and cognitive psychology, her master’s degree in instructional design, and her certificate in web design have all guided her in writing and presenting information for a wide variety of audiences and uses. Nancy’s service as faculty development coordinator in the Department of Family Medicine at Wright State University also provided experience in medical research, plus insights into medical education and medical care from the professional’s perspective.

Nancy Hepp, MS Lead Researcher

Laura Pole, MSN, RN, OCNS

Senior Clinical Consultant
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Laura Pole is senior clinical consultant for CancerChoices. Laura is an oncology clinical nurse specialist who has been providing integrative oncology clinical care, navigation, consultation, and education services for over 40 years. She is the co-creator and co-coordinator of the Integrative Oncology Navigation Training at Smith Center for Healing and the Arts in Washington, DC. Laura also manages the “Media Watch Cancer News That You Can Use” listserv for Smith Center/Commonweal. In her role as a palliative care educator and consultant, Laura has served as statewide Respecting Choices Faculty for the Virginia POST (Physician Orders for Scope of Treatment) Collaborative as well as provided statewide professional education on palliative and end-of-life care for the Virginia Association for Hospices and Palliative Care.

For CancerChoices, Laura curates content and research, networks with clinical and organizational partners, brings awareness and education of integrative oncology at professional and patient conferences and programs, and translates research into information relevant to the patient experience as well as clinical practice.

Laura sees her work with CancerChoices as a perfect alignment of all her passions, knowledge and skills in integrative oncology care. She is honored to serve you.

Laura Pole, MSN, RN, OCNS Senior Clinical Consultant


Susan Yaguda, MSN, RN

Manager at Atrium Health’s Levine Cancer Institute and CancerChoices Clinical Consultant
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Susan Yaguda, MSN, RN, has been a nurse for nearly 40 years, working in a variety of healthcare settings. She currently works in Charlotte, North Carolina, at Atrium Health’s Levine Cancer Institute as the manager for Integrative Oncology and Cancer Survivorship. She works with a multidisciplinary team to deliver holistic, evidence-based support and education for patients and care partners at any point along the trajectory of cancer care. She completed the Integrative Oncology Scholars Program through the University of Michigan in 2020, is certified as an Integrative Health Coach through Duke Integrative Medicine and has a post-graduate certificate in Nursing Education from the University of North Carolina, Charlotte. Susan also was awarded the Planetree International Scholar’s Award in 2018 and was recognized by the Daisy Foundation for Nurse Leadership in 2021. Susan has a particular interest in empowering patients and care partners with knowledge to help drive informed decision making and educating nurses on the benefits of integrative care for patients and self-care. She has presented nationally and internationally on integrative oncology and nursing education.

She and her husband, Mark, have two adult children and a very spoiled foxhound. She enjoys hiking, knitting, cooking, and pickleball.

“As a frequent consumer of Beyond Conventional Cancer Therapies, and now CancerChoices, for both professional education and patient support, it is an honor to have the opportunity to engage with the dedicated team at CancerChoices to serve those impacted by this disease.”  


Susan Yaguda, MSN, RN Manager at Atrium Health’s Levine Cancer Institute and CancerChoices Clinical Consultant

Last update: May 9, 2024

Last full literature review: May 2023

CancerChoices provides information about integrativein cancer care, a patient-centered approach combining the best of conventional care, self care, and evidence-informed complementary care in an integrated plan cancer care. We review complementaryin cancer care, complementary care involves the use of therapies intended to enhance or add to standard conventional treatments; examples include supplements, mind-body approaches such as yoga or psychosocialtherapy, and acupuncture therapies and self carelifestyle actions and behaviors that may impact cancer outcomes; examples include eating health-promoting foods, limiting alcohol, increasing physical activity, and managing stress practices to help patients and professionals explore and integrate the best combination of conventionalthe cancer care offered by conventionally trained physicians and most hospitals; examples are chemotherapy, surgery, and radiotherapy and complementary therapies and practices for each person.

Our staff have no financial conflicts of interest to declare. We receive no funds from any manufacturers or retailers gaining financial profit by promoting or discouraging therapies mentioned on this site.

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