Clinical and fiscal impact of lansoprazole intolerance in veterans with gastro‐oesophageal reflux disease

Abstract

Background: Omeprazole was replaced by lansoprazole as the only proton pump inhibitor on the Veterans Affairs (VA) formulary in February 1997. We aimed to assess the clinical and fiscal impact of this conversion at two VA hospitals. Methods: We identified lansoprazole intolerant patients using pharmacy databases. We reviewed medical records to obtain data regarding reasons for lansoprazole intolerance. The costs of the formulary change and the savings to the VA were calculated. Results: A total of 3833 patients required long‐term proton pump inhibitor therapy; 2224 (58%) were started on lansoprazole and 1479 (39%) were converted from omeprazole to lansoprazole. The remaining 130 (3.4%) patients were never converted from omeprazole to lansoprazole. Of the 3833 patients, 325 (8.5%) currently receive omeprazole therapy; of these, 195 out of 3703 (5.3%) patients are true lansoprazole failures; 172 of these 195 patients completed the study. Most (87%) of the lansoprazole intolerant patients received prior omeprazole. Discontinuation of lansoprazole was due to poor symptom control in 69% and/or side‐effects (22%) including diarrhoea (10%), abdominal pain (5%), or hives (1%). The 1‐year cost of managing lansoprazole failure in 195 patients was $61 690. However, the savings to the VA during the same time period, which totalled $321 360, more than offset the costs associated with the conversion. Conclusions: Lansoprazole intolerance requiring omeprazole conversion occurred in 5% of veterans on proton pump inhibitor therapy for chronic gastro‐oesophageal reflux disease (GERD) symptoms and in 10% of patients with prior omeprazole success. The VA realized substantial cost savings in association with the formulary change.

Failures in a Proton Pump Inhibitor Therapeutic Substitution Program: Lessons Learned

“…It has been our anecdotal experience that with each antisecretory drug substitution program performed at our hospital (e.g., cimetidine to ranitidine, ranitidine to nizatidine, omeprazole to lansoprazole [LAN], LAN to rabeprazole [RAB]), some of our patients have complained that the new drug was less effective and have requested to be switched back. This experience is similar to that reported by other hospitals [4][5][6][7]. For example, at the Palo Alto VA hospital, approximately 10% of veterans who were switched from omeprazole to LAN were subsequently switched back.…”

“…Twenty-one percent of the patients switched back [5]. Another study examined data obtained at a single time point and found a similar proportion with increased symptoms (29%) but the proportion increased was balanced by those who reported symptom improvement [4,7] with no change in median symptom score. Overall 78% were satisfied or neutral about the exchange.…”

“…Therapeutic failure has been defined as failure because of side effects or no response [6]. There are a number of potential causes of therapeutic failure leading to a switch back to the original medication including physiological differences such as differences in potency or pharmacokinetic profiles among the PPIs, resulting in a reduced acid inhibitory effect [4]. There may also be a number of psychological barriers affecting the willingness to change including the perception of differences in effectiveness by either the patient or the physician or other biases toward a particular drug on the part of the patient or physician.…”

“…For example, at the Palo Alto VA hospital, approximately 10% of veterans who were switched from omeprazole to LAN were subsequently switched back. The primary reason given by the patients was lack of effectiveness of the new proton pump inhibitor (PPI) [4].…”

Medication Side Effects: Barriers to the Management of Fluid Intake

“…This has the potential to add further complication because certain PPIs can occasionally cause diarrhea and in rare cases cause colitis. 39,40 …”