Related Experiment Video
Updated: Jul 18, 2026

Targeting the Rat's Small Bowel: Long-Term Infusion into the Superior Mesenteric Artery
Published on: April 8, 2021
Is absorption of oral contraceptives affected by intestinal bypass for obesity?
Question:
Please discuss the effectiveness of oral contraceptives in women who have undergone intestinal bypass surgery for obesity. Is there sufficient steroid absorption to prevent pregnancy?
Answer:
I am not aware of any data on the absorption of oral contraceptives in patients with an intestinal bypass. The effectiveness of oral contraceptives depends on the amount of estrogen and progestin administered, and decreasing the dosage to too low a level will increase the likelihood of pregnancy. Since the bypass will substantially reduce the absorptive area, it is quite possible that effective steroid absorption would not be obtained. In the absence of a study demonstrating adequate steroid absorption in this type of patient, in my opinion a contraceptive procedure other than oral contraceptives should be advised.
Related Concept Videos
Drug Absorption: Factors Affecting GI Absorption
In...
Drugs for Treatment of Constipation-Predominant IBS
Factors Influencing Drug Absorption: Anatomical Parameters
Factors Influencing Drug Absorption: Disease States and Pharmacology
Substances such as alcohol and specific drugs, including antineoplastics, can also negatively impact drug absorption. For instance,...
Pharmacokinetics in Obese Patients: Drug Absorption and Distribution
Pharmacokinetics in Obese Patients: Drug Metabolism and Excretion

