Pentazocine Cuts Acute Pancreatitis Pain Better Than Diclofenac

By Lorraine L. Janeczko

May 17, 2019

NEW YORK (Reuters Health) - In acute pancreatitis, the opioid pentazocine relieves pain better than the nonsteroidal anti-inflammatory drug (NSAID) diclofenac, a randomized controlled trial from India shows.

"This study is a useful addition to our knowledge of this difficult disease by a respected clinical research group," Dr. David Carr-Locke, clinical director of the Center for Advanced Digestive Care at NewYork-Presbyterian/Weill Cornell Medical Center in New York City, told Reuters Health by email.

"These results are not really surprising," added Dr. Carr-Locke, who was not involved in the study. "Despite their theoretical negative effects in this clinical situation, narcotics are always more powerful pain relievers than NSAIDS, and pain relief was the primary endpoint of this study."

Dr. Pramod Kumar Garg and colleagues at All India Institute of Medical Sciences in New Delhi treated a group of 24 adult inpatients who had acute pancreatitis with intravenous pentazocine 30 mg and another group of 26 with intravenous diclofenac 75 mg. All participants also had control of a pump that provided fentanyl as a rescue analgesic. Baseline characteristics in both groups were similar.

As reported in The American Journal of Gastroenterology, online April 16, pentazocine outperformed diclofenac in lowering the required dose of fentanyl (126 vs 225.5 ug; P=0.028) and giving patients longer pain-free periods (31.1 vs 27.9 hours; P=0.047).

The number of effective demands, which delivered fentanyl, and ineffective demands, which did not deliver the drug, was somewhat, but not statistically, lower in the pentazocine group than in the diclofenac group (11.5 vs 16; P=0.098).

Two cases of organ failure in the diclofenac group, including one death, were judged unrelated to the medication. Adverse events were similar in both groups, with no major adverse effects of pentazocine and no increase in the severity of acute pancreatitis with its use.

Dr. Sumit K. Singla, a gastroenterologist and the director of Endoscopic Services at Henry Ford Health System in Detroit, told Reuters Health by email, "This study was conducted in a country in which exposure to narcotics is otherwise quite minimal. I would hypothesize that asking Western patients (and physicians) to treat acute pancreatitis with NSAIDSs would be a challenge due to concern and fear about undertreating pain."

"These findings do not surprise me, as opioid medications are considered the gold standard for management of acute and severe pain, which is the sine qua non of acute pancreatitis," said Dr. Singla, who also was not involved in the study.

"This is an important study, as concerns over the opioid epidemic have cast a microscope over the use of opioids for all indications," he added. "I anticipate that similar studies, including the timing of narcotic cessation for patients with pancreatitis, will increasingly be conducted in the near future. For the time being, however, I think short-term narcotics will remain essential for the management of acute pain associated with pancreatitis."

Dr. Carr-Locke noted that the two drugs used in the study "are not popular in the United States for the management of acute pancreatitis pain, so these results will have little significant influence on patient care in the U.S."

The study did not receive outside funding, and the authors declared no competing interests.

Dr. Garg did not respond to requests for comment.


Am J Gastroenterol 2019.