Viberzi (eluxadoline), a product of Teva Pharmaceutical Industries, is a medication designed to treat a specific form of irritable bowel syndrome accompanied by diarrhea (IBS-D). It works by inhibiting the action of certain opioid receptors in the digestive tract while activating others.
As a result of this mechanism of action, food is able to move through the small intestine more efficiently, which in turn, relieves IBD symptoms. A safety study published in December 2016 in the American Journal of Gastroenterology identified a number issues, including what are known as “Sphincter of Oddi Spasm” (SOS) events. These are of particular concern, since these spasms, which occur in patients who have had their gallbladders removed, can have life-threatening consequences.
What Is The “Sphincter of Oddi”?
Named after late-19th Century medical scientist Ruggero Oddi, this organ also is known as the hepatopancreatic sphincter. It is a type pf muscular valve that regulates the flow of digestive juices from the liver and the pancreas into the hepatopancreatic duct, or ampulla. This is where the bile duct from the liver and the duct carrying pancreatic juice come together before entering the first section of the small intestine, or duodendum. Normally, the Sphincter of Oddi (SO) is relaxed, or opened up, through the action of a hormone (cholecystokinin) secreted by endocrine cells in the duodendum.
SOS and Opioids
SOS events can be caused by the use of opioid pain relievers – particularly in patients who have had their gallbladders removed or who have undergone gastric bypass surgery. This association has been known for well over 75 years. In 1941, when the city of London was still subject to periodic air raids during the Second World War, physician J.B. Williamson wrote a letter to the British Medical Journal, expressing his concerns after reading a publication by a colleague who found that certain opioid medications caused SOS events in patients who had undergone a cholecystectomy (gallbladder removal). Noting that such a patient had experienced severe pain after taking a small dose of codeine, Williamson wrote:
“There must be in the country a fair number of people without gallbladders...if they become casualties, a full dose of morphine will probably be administered by a doctor who knows nothing of their medical history. One supposes that, far from relieving their pain and shock, this may increase it.”
A study from 2001 looked at the effect of narcotics such as morphine and codeine on SO function, and found that “...the SO is exquisitely sensitive to all narcotics...[which] interfere with SO peristalsis [the constriction and relaxation of muscle tissue].”
Viberzi and SOS
In March 2017, the U.S. Food and Drug Administration issued a Drug Safety Communication regarding serious hospitalizations and deaths associated with Viberzi taken by cholecystectomy patients. In the course of the drug's interactions with the digestive system's opioid receptors, these patients experience severe SOS events. As a result, the digestive enzymes released by the liver and pancreas are activated before they are released into the duodenum – and begin to act on the pancreas, causing acute inflammation (pancreatitis). This, in turn, can cause severe internal injuries affecting vital organs such as the heart, lungs and kidneys.
Given the fact that the effects of opioids on the SO of cholecystectomy patients has been known for decades, the obvious question is why did the manufacturers fail to investigate the possible side effects of a drug designed to interact with opioid receptors? This is the reason that lawsuits are being filed against the manufacturers of Viberzi. To learn more, visit our Viberzi Lawsuit page.