Dr. Timna Naftali

Dr. Timna Naftali

MD Specialist in Gastroenterology at Meir Hospital and Kupat Holim Clinic

Specialist in Gastroenterology at Meir Hospital and Kupat Holim Clinic (Israel)

Not Clearly Pro or Con to the question “Should Marijuana Be a Medical Option?

“Tetrahydrocannabinol is safe and has beneficial effects, including steroid sparing, in moderately active Crohn’s disease.”
Presentation, “Tetrahydrocannabinol (THC) Induces Clinical and Biochemical Improvement with a Steroid Sparing Effect in Active Crohn’s Disease,” 2012 American Gastroenterology Association conference

Theoretical Expertise Ranking:
Key Experts
Physicians [Physicians are the “key experts” in the medical marijuana debate because the issue is thought by many to be ultimately based on the medical value and risks of marijuana, and Physicians, with their training and clinical work, should (at least in theory) have the best knowledge of marijuana’s medical value and risks.] [Note: Key Experts definition varies by sites that have this designation.]

Involvement and Affiliations:

  • Specialist in Gastroenterology, Meir Hospital and Kupat Holim Clinic, Jan. 1998-present
  • Member, American Gastroenterology Association, 2001-present
  • Member, Israeli Forum of Neurogastroenterology, 1999-present
  • Treasurer, Israeli Gastroenterology Association, member since 1995
  • Resident, Department of Gastroenterology and Liver Diseases, Meir Hospital, Kefar Saba, May 1995-1997
  • Manager, Department of Internal Medicine “D”, Meir Hospital, Kefar Saba, 1993-1995
  • Senior Doctor, Community Clinic, Tel Aviv (Israel), 1993
  • Resident, Department of Internal Medicine “C,” Meir Hospital, Kefar Saba, 1988-1992
  • Intern, Meir Hospital, Kefar Saba, 1986-1987
  • Nurse, Department of Medicine, Ichilov Hospital (Israel), 1982-1983
  • Exchange Student, Neurological ICU, Sloan Kettering (New York), summer 1982
  • Nurse, ICCU, Beilinson Hospital (Israel), 1981-1982
  • Service in Israeli Military, 1976-1978


  • Certification in Gastroenterology, Israel Scientific Council, 1998
  • Certification in Internal Medicine, Israel Scientific Council, 1992
  • Studied medicine, Sackler School of Medicine, Tel Aviv University (Israel), 1980-1986
  • Studied chemistry, Hebrew University, Jerusalem (Israel), 1979

Contact Info:                                       Phone: 972-9-7472580
Fax: 972-9-7472725
Email: naftali@post.tau.ac.il
Website: University profile

 Select Publications:

  • “Medical Cannabis: The Opportunity versus the Temptation,” Harefuah, Dec. 2011
  • “Treatment of Crohn’s Disease with Cannabis: An Observational Study,” Israel Medical Association Journal, Aug. 2011
  • Ziziphus Jujuba Extract for the Treatment of Chronic Idiopathic Constipation: a Controlled Clinical Trial,” Digestion, Feb. 2009
  • Cowritten with O. Goldstein and Y. Shaham, “Toilet Reading Habits in Israeli Adults,” Neurogastroenterology and Motility, Mar. 2009
  • “Interleukin-18 and Its Binding Protein in Patients with Inflammatory Bowel Disease during Remission and Exacerbation,” Israel Medical Association Journal, Aug. 2007
  • Cowritten with E. Niv, et al., “The Efficacy of Lactobacillus Reuteri ATCC 55730 in the Treatment of Patients with Irritable Bowel Syndrome–a Double Blind, Placebo-controlled, Randomized Study,” Clinical Nutrition, Dec. 2005
  • Cowritten with R. Towers, et al., “High Levels of Glucocorticoid Receptors in Patients with Active Crohn’s Disease May Predict Steroid Resistance, Clinical & Experimental Immunology, Aug. 2005


  • Active participant in numerous scientific meetings including the Congress of the European Crohn’s and Colitis Organisation in Vienna in 2013 and the Digestive Disease Week in San Diego, CA in 2012
  • Married with four children

Quoted in:
1. Is Marijuana an Effective Treatment for Crohn’s Disease, Ulcerative Colitis, or Other Inflammatory Bowel Diseases?