Dissolution of Common Psychiatric Medications in a Roux-en-Y Gastric Bypass Model

Department of Psychiatry and Behavioral Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73151, USA.
Psychosomatics (Impact Factor: 1.86). 05/2005; 46(3):250-3. DOI: 10.1176/appi.psy.46.3.250
Source: PubMed


Large numbers of Roux-en-Y gastric bypass (RYGB) surgery patients have psychiatric illnesses that are in part treated with medication preoperatively, but there are no objective data to guide psychiatric drug dosing postoperatively. An in vitro drug dissolution model was developed to approximate the gastrointestinal environment of the preoperative (control) and post-RYGB states. Medication tablets were placed in the two environments, and the median calculated weights of the dissolved portions were compared. Ten of 22 psychiatric medication preparations had significantly less dissolution and two had significantly greater dissolution in the post-RYGB environment, compared with the control environment. The results suggest a need for an in vivo study of serum drug levels after RYGB surgery in patients taking psychiatric medications. Differences in the pharmacokinetics of the postoperative RYGB patient may necessitate adjustments in dosing.

1 Follower
70 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: The pharmacokinetics of escitalopram (S-citalopram) and its principal metabolite, S-demethylcitalopram (S-DCT), were investigated after intravenous and oral administration to healthy subjects. After intravenous infusion of escitalopram, the mean systemic clearance and volume of distribution were 31 L/h and 1,100 L, respectively. After oral administration of single or multiple doses, the absorption was relatively fast, with the maximum observed plasma or serum concentration (C(max)) attained after 3 to 4 hours. The mean half-lives were 27 and 33 hours, respectively; steady state was attained within 10 days. The area under the plasma or serum concentration time curve from time zero to 24 hours and C(max) was both linear and proportional to the dose. The apparent volume of distribution was around 20 L/kg. Comparison of the systemic and oral clearance implied a high absolute bioavailability. There was no evidence of interconversion from S-citalopram to R-citalopram either in plasma or in urine. Concurrent intake of food had no effect on the pharmacokinetics of escitalopram or its metabolite. All treatments were well tolerated.
    The Journal of Clinical Pharmacology 01/2006; 45(12):1400-6. DOI:10.1177/0091270005280860 · 2.48 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The number of bariatric surgical procedures performed in the United States has increased steadily during the past decade. Currently accepted criteria for consideration of bariatric surgery include a body mass index (calculated as weight in kilograms divided by the square of height in meters) of 40 kg/m2 or greater (or >35 kg/m2 with obesity-related comorbidities), documented or high probability of failure of nonsurgical weight loss treatments, and assurance that the patient is well informed, motivated, and compliant. Appropriate patient selection is important in achieving optimal outcomes after bariatric surgery. In this article, we review our approach to the medical and psychological assessment of patients who want to undergo bariatric surgery. The medical evaluation is designed to identify and optimally treat medical comorbidities that may affect perioperative risks and long-term outcomes. The psychiatric and psychological assessment identifies factors that may influence long-term success in maintaining weight loss and prepares the patient for the lifestyle changes needed both before and after surgery.
    Mayo Clinic Proceedings 11/2006; 81(10 Suppl):S11-7. DOI:10.1016/S0025-6196(11)61176-2 · 6.26 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: More than half of gastric bypass patients take antidepressants preoperatively, presenting some unique considerations with this patient population. The challenges associated with antidepressant medications are experienced both preoperatively and postoperatively. As the gastric bypass option becomes more readily used in the treatment of obesity, the requirement for understanding the effect of this procedure on any alteration of medications will become more clinically important. The purpose of this paper is to present an overview of the potential challenges in providing optimal patient care for the gastric bypass patient who is taking antidepressant medications.
    Journal of PeriAnesthesia Nursing 04/2007; 22(2):108-21; quiz 122-4. DOI:10.1016/j.jopan.2006.11.005 · 0.94 Impact Factor
Show more

Similar Publications


70 Reads
Available from