for people ages 18-64 (full criteria)
healthy people welcome
at San Francisco, California
study started
estimated completion
Leslie Z Benet Lynda A Frassetto



Food will decrease stomach acidity due to its buffering effect.This has implications when providing drugs that are dosed with food but require higher levels of stomach acid, such as some medications commonly used for HIV patients. This study will attempt to determine the dose of betaine hydrochloride (over the counter acid supplement) at which the effect of food on stomach acid could be countered. Additionally, this study will evaluate the ability of a natural supplement (betaine hydrochloride) to affect the gastric pH following a standardized meal in healthy volunteers. The investigators predict that 4500mg of betaine hydrochloride will have the greatest effect on gastric pH.

Official Title

Countering the Gastric ph Effect of a Standardized Meal in Healthy Volunteers Using Clinical Doses of Betaine Hydrochloride


Healthy betaine betaine hydrochloride healthy volunteer gastric pH Standardized Meal Betaine Hydrochloride 1500mg Betaine Hydrochloride 3000mg Betaine Hydrochloride 4500mg Beatine PO (by mouth) 1500mg Betaine PO (by mouth) 3000mg Betaine PO (by mouth) 4500mg


You can join if…

Open to people ages 18-64

  • Male or female 18-64 years of age;
  • Healthy adult with no active medical problems or significant chronic diseases as determined by the study doctor based on history, physical exam;
  • BMI between 18.5 - 32 kg/m2;
  • Taking no medications 2 weeks before and during the study enrollment, including drugs of abuse, prescription or OTC medications (except acetaminophen);
  • Be able to provide written informed consent and comply with requirements of the study;
  • Avoid eating grapefruit and drinking grapefruit juice from 7 days before the first study day until completion of the entire study;
  • Abstinence from alcoholic beverages, caffeinated beverages and orange juice from 3pm the night before a study day until completion of that study day;
  • Fast from food and beverages at least 8 hours prior to the study day;
  • Be able to read, speak and understand English

You CAN'T join if...

  • Subjects with a history of gastrointestinal disease including gastroesophageal reflux disease, gastritis, peptic ulcer disease or dyspepsia.
  • Subjects with a fasting gastric pH of > 4 (i.e. hypochlorhydria)
  • Subjects with history of dysphagia, achalasia, or difficulty swallowing capsules, tablets or pills.
  • Subjects on prescription or chronic over-the counter medications (including hormonal contraceptives);
  • Subjects with liver failure or LFTs >2x upper limit of normal;
  • Subjects with clinically significant elevations in SCr, BUN or other screening laboratory tests as determined by study physician;
  • Subjects with Hct < 30 mg/dL, WBC < 2000/μL, ANC < 1000/μL, or platelet count < 150,000/μL;
  • Subjects with a history or presence of an abnormal ECG, including demonstration of a baseline corrected Fridericia's QT interval (QTcF) >450ms, which in the opinion of the study physician, is clinically significant;
  • Subjects who smoke tobacco;
  • Subjects with ongoing alcohol or illegal drug use;
  • Subjects who are pregnant, lactating or attempting to conceive;
  • Subjects unable to follow protocol instructions or protocol criteria.
  • Anyone who in the opinion of the study investigators is unable to participate in the study.


  • Clinical Research Center, UCSF
    San Francisco California 94143 United States

Lead Scientists


in progress, not accepting new patients
Start Date
Completion Date
University of California, San Francisco
Study Type
Last Updated