Effect of Gastric Bypass on the Absorption of Metformin

NCT ID: NCT01013051

Last Updated: 2011-03-03

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 34 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2009-09-30
• Study Completion Date: 2010-12-31

Brief Summary

Background: Gastric bypass is the most commonly performed type of bariatric (obesity) surgery, has dramatically increased in popularity and is now considered to be preferred treatments in severely obese patients that fail non-surgical therapy - particularly in patients with type 2 diabetes. Drug malabsorption is a potential concern post-gastric bypass because intestinal length is reduced.

Purpose: The purpose of this controlled, pharmacokinetic study is to determine whether the absorption of a single dose of metformin, the first line drug treatment in patients with type 2 diabetes, is significantly reduced after gastric bypass.

Methods: A single dose of standard release metformin 1000 mg will be administered to patients who have undergone gastric bypass and to patients who have not received surgery but are on the wait list (wait-listed controls). Blood sampling and urine sampling will occur in standardized fashion over the ensuing 24 hours to measure and compare the absorption of metformin between study arms. 34 patients total will be recruited.

Significance: Following completion of this study, we will better understand how gastric bypass affects metformin absorption. Ultimately, this information will help to ensure that this patient population is receiving optimal doses of this important drug treatment.

Conditions

Obesity; Gastric Bypass

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: PROSPECTIVE

Study Groups

Post Gastric Bypass

No interventions assigned to this group

Obese Controls

age, BMI, gender matched

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

Patients living within and around Edmonton that have been referred to the Alberta Health Services Weight Wise Program

Exclusion Criteria

1. Undergone or undergoing revision of a previous bariatric procedure

2. Any major post-operative gastrointestinal complications, such as an anastomotic leak, outlet obstruction or persistent vomiting

3. Currently on metformin therapy

4. Any contraindications to metformin therapy such as:

1. allergy to the drug

2. chronic metabolic acidosis

3. history of lactic acidosis

4. liver failure or baseline liver enzymes higher than 3-fold above the upper limit of normal

5. congestive heart failure

6. renal failure (glomerular filtration rate < 60 ml/min)

7. alcoholism

8. acute illness

9. fatty liver disease

5. Pregnant or nursing

6. Not taking furosemide or nifedipine (both drugs may increase metformin absorption by 15-20%)the day of visit 2.

7. Any other medical, social or geographic condition, which, in the opinion of the investigator would not allow safe completion of the study protocol

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Alberta

OTHER

Sponsor Role: lead

Responsible Party

University of Alberta

Principal Investigators

Raj Padwal, MD

Role: PRINCIPAL_INVESTIGATOR

University of Alberta

Locations

University of Alberta Hospital Clinical Investigation Unity

Edmonton, Alberta, Canada

Countries

Canada

Other Identifiers

RES0002122

Identifier Type: -

Identifier Source: org_study_id