Absorption of Drugs Post-Bariatric Surgery (Absorb-Azithromycin)

• Status: Completed
• Trial end date: 2011-07-01
• Target enrollment: 0
• Participant gender: All

Summary

Bariatric (obesity) surgery has become the preferred treatment option for patients with severe obesity and is increasing in popularity. It is commonly performed, with nearly 350 000 operations in the world every year. The most common type of bariatric surgery is gastric bypass, in which stomach size is reduced by 95% and the upper intestine is bypassed. Bypass of the upper intestine may lead to medication malabsorption, although this potential adverse effect has received little study.

The objective of this study is to determine whether gastric bypass reduces the absorption of a azithromycin, a medication commonly prescribed first-line for infections, especially pneumonia. Patients and non-surgical controls will receive a single dose of azithromycin under highly standardized study conditions. The absorption of azithromycin will be calculated and compared between surgical and non-surgical study groups.

The investigators hypothesis is that there will be a significant reduction in the absorption of azithromycin in gastric bypass patients compared to non-surgical controls. This raises the possibility that post-gastric bypass patients treated with azithromycin may fail to respond to treatment, become worse and even die. This study will have important implications for the large number of past and future gastric bypass recipients.

• Phase: N/A
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: University of Alberta
• Treatments: Azithromycin

Criteria

Inclusion Criteria:

1. Male and Female

2. 18 - 60 years old

3. ≥ 3 months post-RYGB surgery or a suitable control for bariatric surgery

4. Able to provide written informed consent.

Exclusion Criteria:

1. Undergone or undergoing reversal of a previous bariatric procedure which involves further resection or bypass of the intestine.

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

3. Currently on azithromycin therapy

4. Any contraindications to azithromycin therapy such as:

• Allergy or hypersensitivity to the drug

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

• end-stage renal failure (glomerular filtration rate < 10 ml/min)

• macrolide hypersensitivity

• history of torsade de pointes or baseline QTc interval ≥ 500 ms

• acute illness

5. Pregnant or nursing

6. Concomitant treatment with septra, anti-HIV drugs, digoxin, disopyramide, ergotamine, dihydroergotamine, triazolam, antihistamines (terfenadine, astemizole) and theophylline is also a contraindication to enrolment because of the potential for drug interactions that would affect the blood concentrations of azithromycin or these agents.

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