Gastric bypass patients are typically advised against using extended release medications. Extended release medications are popular because they only need to be taken once or maybe twice a day instead of several times a day. For example, the antidepressant Effexor XR (XR means extended release) only needs to be taken once a day; a patient can take 300 mg at one time. Effexor also comes in a non-extended release tablet, but a patient would need to take a 75 mg tablet four times a day instead of taking two 150 mg capsules once a day. It’s more convenient to take a medication just once a day.
Extended release medications are designed to dissolve and be absorbed slowly, over a period of about 14 to 24 hours. The reason they don’t work well for gastric bypass patients is because our digestive tract is shorter than a “normal” digestive tract. Since we do not have a pyloric valve between our pouch and our small intestine, pills won’t stay in our pouch as long as they would stay in “normal” stomach. Then, since part of our small intestine has been bypassed, it does not take pills as long to work their way through the small intestine as it does in a “normal” small intestine. Pills are unlikely to remain in our digestive tract for 12 hours or more; therefore, we would absorb some of the medication but not the full amount.
Taking extended release medications won’t necessarily hurt you after gastric bypass surgery, but they may not help you much, either. You will not get the full benefit of the medication. Most extended release medications are available in non-extended release versions. If you take a medication not available in a non-extended release version, ask your doctor if there is an alternative medication you could take instead. If you’re not sure if a medication is an extended release drug or not, ask your doctor or pharmacist. While bariatric surgeons are usually aware that gastric bypass patients don’t absorb extended release medications properly, other physicians may not be aware of this. Make sure any doctor prescribing medication for you knows that you need non-extended release drugs.