NEW YORK (Reuters Health) – An observational study conducted in the Netherlands finds that unexplained acute pancreatitis is often associated with drugs that can cause the condition, but the relationship is not always recognized.

“Physicians should be more aware of the possibility of drug-induced pancreatitis in patients with otherwise unexplained acute pancreatitis and act appropriately by discontinuation of the drug,” conclude the authors of the report in the American Journal of Gastroenterology online September 13.

In their introduction, Dr. B.W. Marcel Spanier, at Rijnstate Hospital in Arnhem, and colleagues explain that drug-induced pancreatitis is thought to be rare but the true incidence is unknown. The latest list of drugs linked to pancreatitis, they continue, includes 120 medications classified based on the strength of the evidence for an association.

Class I includes drugs with at least one case report and documented recurrence after rechallenge; class II includes drugs with at least four cases reported and consistent latency; class III denotes those with at least two case reports and no latency or rechallenge data; and class IV includes those with just one case report and no rechallenge data.

To evaluate the prevalence of possibly drug-induced acute pancreatitis, the team conducted a prospective observational study of 168 consecutive patients hospitalized with acute pancreatitis at 18 hospitals in northern Holland.

The investigators found that 70 of the patients used a pancreatitis-associated drug and in 44 (26%) of those cases the drug was in the class I category. The most frequently used class I drugs were simvastatin, enalapril and omeprazole, according to the report.

Ultimately, the researchers determined that pancreatitis was possibly drug-induced in 21 instances (12.5%), but in only 9 of these cases was the drug discontinued with no recurrence of acute pancreatitis. Based on these numbers, the prevalence of drug-induced pancreatitis was 5.4% (i.e., 9 out of 168 cases).

Conversely, the drug was not discontinued 12 of the 21 cases, even though a class I agent was involved in 8 of those cases, Dr. Spanier and colleagues point out.

“In this series, a remarkably high percentage of patients who were admitted because of an attack of acute pancreatitis used pancreatitis-associated drugs,” they conclude.

The authors add, “Larger epidemiological studies are warranted to establish the true risk of acute pancreatitis for various drugs using a uniform and widely accepted drug-induced pancreatitis classification system.”

Reference:
Acute Pancreatitis and Concomitant Use of Pancreatitis-Associated Drugs
Am J Gastroenterol 2011.