by Brooke Keefer
Read about the most commonly used medications prescribed for Sphincter of Oddi Dysfunction (SOD) as gathered from patient surveys, support group input, and research articles.
Medications can be beneficial in alleviating Sphincter of Oddi Dysfunction (SOD) symptoms like pain and nausea. The course of treatment a physician commonly takes for SOD relief, after diet and lifestyle modifications fail, is prescribing a medication. Often, finding the right medication takes trial and error. Over the years I have witnessed profound variations regarding medication success in each SOD patient. One woman will tell you she gets complete relief from a calcium channel blocker, antispasmodic, or other medication while these same medications offer no relief for others. Some tolerate side effects while others cannot get past a single dose.
There are medications for almost every digestive condition. Although many people with SOD also have other co-occurring digestive issues like ulcerative colitis, Crohn’s disease, acid reflux, irritable bowel syndrome, and small intestinal bacterial overgrowth to name a few, I will focus on medications commonly prescribed for SOD symptoms rather than disorders. I use United States generic drug names. If you are from a different country, you should easily be able to find their counterparts by searching online. This is by no means a complete list. The information here was compiled from SOD patient surveys, support group input, and research articles.
Anticholinergics and Antispasmodics
Anticholinergics interfere with the action of the neurochemical acetylcholine and block involuntary movements. They stop the transmission of parasympathetic nerve impulses therefore lessening the spasms of smooth muscle, such as in the gastrointestinal tract and in the bladder. Most antispasmodic agents are also anticholinergics. They can work directly on the smooth muscle in the wall of the gut. Here they help to relax the muscle and relieve the pain associated with a contraction of the gut.
Since the sphincter of Oddi is a tiny smooth muscle it is thought this class of drugs will prevent the sphincter from spasm and quell the nerve pain associated with SOD. I have witnessed many SOD sufferers gain relief by taking this class of drugs. In addition to SOD pain, these drugs may be prescribed for biliary colic (spasm) and nausea. Side effects are generally minimal, but for some become intolerable. The most common are mucous membrane dryness, dizziness, and drowsiness. Examples of anticholinergic/antispasmodic agents are: hyoscyamine, chlordiazepoxide/clidinium, dicyclomine, scopolamine, glycopyrrolate, amitriptyline, nortriptyline, atropine, mebeverine (not available in the U.S.), and combos of these generics with phenobarbital and belladonna.
Muscle relaxants are agents that reduce tension in muscles. Centrally acting muscle relaxants work by reducing the tone of skeletal muscle causing muscles to relax. These are generally used to relieve skeletal muscle spasms due to spastic conditions, and can be used to relieve musculoskeletal pain. Some muscle relaxers also work by blocking pain sensations between the nerves and the brain.
Like with the anticholinergic/antispasmodic class of drugs, muscle relaxers are prescribed to stop the sphincter of Oddi from spasm and help control the pain related with this tiny little muscle. An interesting observation is the people I know who gained relief from muscle relaxers also got relief from biliary stents and the biliary roux en y surgery, leading me to believe these individuals had issues solely with their biliary sphincter and/or bile duct and not the pancreatic sphincter. Examples of muscle relaxers are: cyclobenzaprine, carisoprodol, baclofen and buscopan. Common side effects are similar to anticholinergics and antispasmodics.
Calcium Channel Blockers
Calcium channel blockers are typically used to treat high blood pressure and heart conditions. They act as a smooth muscle selective calcium channel antagonists and potent inhibitors of sphincter of Oddi contractions. This medication may be particularly helpful when a patient is having a painful attack. The downside is its effect on blood pressure. If someone has low or even normal blood pressure, these medications can cause a severe drop in blood pressure. If you do not have low blood pressure and experience sudden pain attacks, you may want to discuss this medication with your doctor. Examples of calcium channel blockers are: nitroglycerin, nifedipine, diltiazem, amlodipine, and felodipine.
Anti-epileptic Anticonvulsant Medication
This class of drugs was created to mimic some of the effects of GABA, an inhibitory neurotransmitter found in the central nervous system (CNS) that regulates its excitability. These drugs are used with other medications to prevent and control seizures. It is also used to relieve nerve pain. Some gastroenterologists believe SOD pain is a neuralgia/nerve pain. Drugs in this class most often prescribed for SOD are gabapentin and pregabalin. Both drugs can make you drowsy. Reviews are mixed on these for SOD—about half and half. I’ve heard more success stories with pregabalin.
Anti-nausea (Antiemetic) Medications
Anti-nausea/Antiemetic medications are used to control nausea and vomiting. If nausea and vomiting are uncontrollable, oral therapy may not be appropriate and intravenous or suppository administration at a hospital may be necessary. The first type of anti-nausea/antiemetic medication is the 5-HT3 receptor antagonists, which block serotonin receptors in the central nervous system and gastrointestinal tract. The most common 5-HT3 receptor antagonist prescribed for nausea is ondansetron. This drug was once reserved for cancer patients receiving chemotherapy but is now widely used for any type of nausea syndrome, including pregnancy morning sickness. It is most useful because it is non-sedating. Mirtazapine is another example but it is quite sedating and prescribed mostly as an anti-depressant.
The second type of anti-nausea/antiemetic is the dopamine antagonists, which block dopamine receptors. The most commonly prescribed in this class are metoclopramide and domperidone. These are also pro-kinetics, which increase gut motility and can help alleviate symptoms of gastroparesis (slow gut motility). It baffles me that domperidone is not FDA approved in the U.S. but metoclopramide is. Some of metoclopramide’s side effects are serious and dangerous, including tardive dyskinesia, irregular blood pressure, and neuroleptic disorders. There are a few SOD patients who say they take it with no side effects. Just be careful, that’s all. Domperidone has not been approved here because it caused some heart irregularities in those receiving it intravenously in very large amounts. It also raises levels of the hormone prolactin which is why some use it to increase breast milk supply. Domperidone, however, can be acquired by prescription if made by a compounding pharmacy. There are also several websites where it can be ordered.
Antihistamines (H1 histamine receptor antagonists) are used off label for nausea and vomiting but carry drowsiness as a side effect. Most antihistamines can be purchased over the counter like diphenhydramine, meclizine, and dimenhydrinate. The more sedating brands require a prescription, ex. promethazine and hydroxyzine.
Many with SOD have bile reflux and/or biliary sludge issues. Bile reflux occurs when bile refluxes up into the stomach causing burning pain and nausea. With sphincter dysfunction, bile can be released at the wrong time and travel upwards into the stomach. Many doctors prescribe proton pump inhibitors (PPIs) or acid reducers, which are indicated for acid reflux or excess stomach acid. Bile reflux is completely different from acid reflux. In addition, when bile enters the stomach it reduces stomach acid. You want a good amount of stomach acid to properly digest proteins and metabolize certain vitamins and minerals.
Cholestyramine is a helpful medication for bile reflux as it binds to bile and carries it out of the body through the feces. It is usually prescribed for bile acid diarrhea, a well-documented problem for people with post-gallbladder issues like SOD. Cholestyramine is gritty and doesn’t taste all that great, but it has been a miracle drug for some with severe bile acid issues. People with high cholesterol will benefit from this drug as it also lowers blood cholesterol levels. Another medication which may help is sucralfate. Sucralfate is chalky and mops up acids.
Biliary sludge is a common issue for people with SOD. Bile becomes thick and sludge-like when it develops microscopic gallstone crystals. No one knows exactly why this happens but for those without a gallbladder it could be the result of bile not flowing properly. Also, when the sphincters spasm and stay shut for long periods, bile gets backed up. A medication called ursodeoxycholic acid may be used to dissolve these microscopic gallstones and “thin” the bile.
Prescription Pancreatic Enzymes
When my SOD pain shifted and spread to the mid-area of my gut under my sternum and under my left rib cage, a gastroenterologist thought the pain could be from my pancreas. Although my imaging studies at the time were perfect, he tried me on prescription enzymes (pancrealipase). Within a week the pain was nearly gone, as long as I took the pills with meals and snacks. Several months later I found out from an ERCP my pancreatic sphincter pressures were very high.
I know many people with SOD who say they wouldn’t be able to work or function if not for marijuana or marijuana derivatives. They laud its miraculous ability to improve pain, nausea, anxiety, stress, etc. Problem is it isn’t legal everywhere so the pot you just purchased from your brother in law’s “connection” may not be an appropriate strain for your SOD symptoms. If you purchase medical marijuana in a legal state, your chances of obtaining a “perfect match” strain for your symptoms increase dramatically. I wouldn’t attempt to recommend a strain and will leave that up to the experts. The only suggestion I can give you is if you use marijuana medicinally, be careful ingesting it as it could exacerbate your digestive issues. Vaporizing or using an oil may be the best option. There is also marijuana in a pill your doctor can prescribe called Dronabinol.
It is thought there is a high degree of COX-2 expression in the smooth muscle cells of the bile duct and sphincter of Oddi. Cyclooxygenase (COX) is an enzyme that is responsible for formation of inflammatory and vasodilating hormones like prostaglandins. Celecoxib is a selective inhibitor of COX-2. It inhibits COX-2 activity in the smooth muscle cells of the biliary tract and the sphincter of Oddi and may help SOD pain.
Opioid Pain Medication
Most opioid pain medications carry “spasm of sphincter of oddi” as a side effect. Some, though, are definitely worse than others. Morphine was used several decades ago to test for SOD spasm (called the Nardi test), so you may want to stay away from that one. Other opioid pain medication may exacerbate the spasm but most SOD patients I know seem to do ok with oxycodone, hydrocodone, or hydromorphone. Intravenous fentanyl and fentanyl patches seem to be best tolerated by those with SOD. Some report success with tramadol, which is supposed to be less addictive than the other opioids. Not only is it an opioid, it inhibits the reuptake of serotonin and norepinephrine, which means it has a slight antidepressant quality to it.
Opioid pain medication is meant for acute pain and short term use and is addictive. However, anyone who has had a severe chronic pain condition like SOD knows that may not be realistic and opioid treatment difficult to obtain. There are several dilemmas these drugs present, including their addictive nature, the opiophobic trend of doctors, and criminalization of these drugs. The SOD patients I know who rely on pain medication and are successful in their use of it are closely monitored by a pain management doctor. They are routinely drug tested and allotted a certain amount so they do not abuse the drugs. Unfortunately, in today’s day and age most SOD patients are treated as drug seekers or refused pain management as they do not have something life threatening like cancer. SOD is poorly understood by most pain doctors. They cannot grasp that SOD can be as painful as cancer pain and in some cases more painful.
Benzodiazepines have multiple clinical uses including therapy of anxiety, insomnia, muscle spasm, alcohol withdrawal and seizures. The pharmacological effects of the benzodiazepines are a result of their interaction with the neurotransmitter GABA receptors and central nervous system, their effects being sedation, hypnosis, decreased anxiety, muscle relaxation, anterograde amnesia and anticonvulsant activity. Benzodiazepines especially affect the digestive system which is loaded with GABA receptors. They can be very useful drugs for SOD nausea, vomiting, dizziness, and to ameliorate the stress and anxiety associated with this syndrome. Some are short acting, like alprazolam and lorazepam. Others, like clonazepam and diazepam, are long acting.
Sounds like a wonder drug, right? Let me tell you they are not. The downside is benzodiazepines are highly addictive and withdrawal effects can last weeks, months, and even years. Your tolerance can build up so you require more and more. The horror stories of interdose withdrawal and withdrawal syndrome are prevalent on the Internet. Please educate yourself about this class of drugs by going to www.benzobuddies.org. Benzodiazepines are recommended for occasional and short term use yet they are prescribed long term. I believe this class of drugs was to blame for pancreatic flares years after my sphincteroplasty as well as a whole host of nervous, digestive and endocrine system issues.
Medication Safety and Side Effects
Ask your doctor if there are black box warnings for any medications prescribed to you and what the most common side effects are. Get to know your pharmacist and let him or her know you want to be alerted of possible drug interactions and severe side effects. Also ask your pharmacist to alert you if “spasm of sphincter of oddi” is a side effect of any drug you are prescribed. I just discovered a few days ago that a side effect of acetaminophen is spasm of sphincter of oddi. I thought the only medications I needed to worry about were opioid pain medications. Not the case.
Remember, doctors and pharmacists don’t always know every side effect and many aren’t listed in the product’s post marketing materials. I can’t tell you how many times a doctor or pharmacist told me a strange symptom I was experiencing could not be from the drug I was taking. Consequently, I would cease taking the drug and the side effect would go away or improve. Always go with your gut instinct. There is a reason .0001% of people get a side effect and the rest of the population don’t. Everyone is unique and thanks to our genetics we metabolize drugs differently.
This article is for informational purposes only. It is not intended to diagnose, treat, cure, or prevent any disease. Please discuss all medications you intend to take with your physician.