Medication Issues

With the unpredictability of absorption of vitamin and minerals following
weight loss surgery, it seems reasonable to be concerned about the
reliability of medication absorption for renal patients. In such a patient,
can one count on the medication absorption necessary to prevent organ
rejection after a kidney transplant?

A pilot study published in 2008 examined the pharmacokinetics of three
modern immunosupressants (mycophenoic acid, tacrolimus, and sirolimus) after
gastric bypass patients with ESRD and post-kidney transplant.They found
that significant differences in dosages were required for RYGB patients
compared with nonbypass population. There was significant interpatient
variability in the RYGB patients group.
Researchers at the University of Oslo studied pharmacokinetics of
atorvastatin in 12 patients with morbid obesity before and following gastric bypass surgery.Variable affects were seen in uptake of the statin.
Researchers concluded that retitration of atorvastatin (compared to
presurgical dose) is necessary following surgery to provide the lowest
effective dose on an individual basis.

A small study of patients who had weight loss surgery following renal
transplantation showed no alterations in the dosages of immunosuppressant
medications that were needed post-bariatric surgery.