Drs. DeMarco and Powell are PGY-1 Psychiatry Residents at Trinity Health, Ann Arbor, Michigan. Ms. Rana and Dr. Ismail are at University of Michigan College of Pharmacy, Ann Arbor, Michigan. Dr. Ward is Clinical Assistant Professor, University of Michigan College of Pharmacy, Ann Arbor, Michigan.
Disclosures Dr. Ward served on the advisory board at BioXcel Therapeutics. The other authors report no financial relationships with any companies whose products are mentioned in this article, or with manufacturers of competing products.
Aside from altered pharmacokinetics after bariatric surgery, many patients experience an increased risk of self-harm and suicide.20 Therefore, a continued emphasis on and reinforcement of proper antidepressant use and adjustment in these patients is important. This can be facilitated through frequent follow-up visits, either in-person or via telehealth.
Understanding the effect of bariatric surgery on drug absorption is critical to identifying a potential need to adjust a medication dose or formulation after the surgery. Available evidence and data suggest it is reasonable to switch from an extended- or sustained-release formulation to an immediate-release formulation, and to monitor patients more frequently immediately following the surgery.
CASE CONTINUED
Immediately following surgery, Ms. B’s care team adjusts her medication regimen. To account for the change in her stomach size and composition, and therefore its absorption process, the team changes the venlafaxine dosage from venlafaxine XR 150 mg daily to venlafaxine immediate-release 75 mg twice daily. Ms. B is also monitored more frequently following the procedure to determine if additional adjustments to her medication dosage or therapy frequency are necessary. Eight weeks following surgery, Ms. B has lost 16 pounds and is reintroducing more solid foods into her diet. She struggles with some increased anxiety and depression approximately 1 month after surgery, but that improves after her clinicians decide to increase the venlafaxine dose to 75 mg 3 times a day. Her lithium level was also monitored more closely for the first month after the procedure to decrease the risk of lithium toxicity.
