Medications for Irritable Bowel Syndrome
There are actually quite a few different prescription medications available for Irritable Bowel Syndrome symptoms, but their effectiveness can vary greatly from one person to the next.[1]
There are also effective non-drug alternatives for IBS, including symptom-specific treatments.
Which particular drug will work best for you is something you'll most likely have to determine through trial and error. Irritable Bowel Syndrome drugs are symptom-specific (aimed at painful abdominal spasms, diarrhea, or constipation), which means they do NOT work on the underlying brain-gut dysfunction of IBS. Only gut-directed IBS hypnotherapy, which has actually been called a "cure" for IBS, can do that.
Medications for IBS are simply meant to relieve your Irritable Bowel Syndrome symptoms. If the first IBS medication you try doesn't help much (or at all), don't be discouraged – there are other options available.
Remember that there's no one particular treatment of choice for Irritable Bowel Syndrome (and no single drug is approved for all IBS symptoms) but many different medications to try.
You should work in partnership with your doctor to determine which medication best fits your needs. This might take a trial period of a few months and several follow-up visits or phone calls. With any new medication, always make sure you receive the clinical insert about health risks, side effects, and possible drug interactions. You may have to specifically ask the pharmacist for this insert (it will be produced by the drug manufacturer) if you don't receive it with your prescription.
Currently, most IBS patients cite great frustration with the lack of safe, reliable and effective Irritable Bowl Syndrome therapies, and would like to see new options made available to them that would have a greater impact on their problem - especially the ability to prevent symptoms. Unfortunately for now, it's mostly a case of better something than nothing at all. So keep your fingers crossed for new medicatons on the horizon.
In general, many people with IBS find the following alternatives as (or even more) beneficial than most IBS medications:
- For IBS diarrhea and/or constipation: soluble fiber supplements
- For IBS pain, spasms, and cramps: medicinal strength peppermint For IBS bloating and gas: medicinal strength fennel
- For global IBS symptoms: the Eating for IBS diet & gut-directed hypnosis
For Irritable Bowel Syndrome Pain
The most frequently prescribed drugs for Irritable Bowel Syndrome IBS pain are Anti-Spasmodics. These drugs affect gut motor activity and reduce the colon's response to both eating and stress. Anti-spasmodics are meant to be taken 30 minutes before eating, but they can also be taken whenever needed . Sublingual (dissolve under your tongue) and oral (swallow whole) varieties are available.
Typically, antispasmodics are prescribed for use four times per day (before each meal and bedtime). Since they have no cumulative effect, however, many patients prefer to take them only as necessary. Donnatal, Levsin, Levbid, NuLev, Bentyl, Mebeverine, Colofac, and Duspatal are common brand names of anti-spasmodics.
Interestingly, clinical studies have shown that enteric coated peppermint oil capsules are as effective as prescription anti-spasmodics for alleviating IBS symptoms, and they do not carry the risk of side effects (dizziness, dry mouth, dry eyes, sleepiness) that prescription anti-spasmodics do.
Low doses of IBS-effective Antidepressants can raise the pain threshold for the painful abdominal cramps of Irritable Bowel Syndrome, and they can also either increase or decrease (depending upon the class of drug) the rate of gastrointestinal contractions as well, thus altering bowel function in either direction (and helping diarrhea or constipation). Why would antidepressants help Irritable Bowel Syndrome? These drugs are meant to affect the uptake of serotonin - a neurotransmitter directly involved in the development of clinical depression - in the brain. However, the enteric nervous system of the gut is also rich with nerves that contain large amounts of serotonin. In fact, 95% of all serotonin in the body is found in the gut, not the brain. So the effect of antidepressants on the brain is felt as a peripheral result in the gut as well.
It's important to note that the dosage of anti-depressants used for Irritable Bowel Syndrome is typically far lower than that of the drug when used for depression. It is also crucial that the doctor prescribing this type of drug be very familiar with its use for IBS, as different classes of anti-depressants have varying side effects. Some can greatly worsen, instead of help, Irritable Bowel Syndrome symptoms such as diarrhea, constipation, and pain, depending on the patient.
In particular, SSRI anti-depressants (Prozac, Celexa, Zoloft and Paxil) stimulate serotonin production and can trigger severe IBS attacks in diarrhea-predominant patients, but they may be helpful for constipation. Conversely, tricyclic anti-depressants (such as Elavil) have the best track record of success for reducing diarrhea-predominant IBS symptoms, but patients with constipation are usually not treated with these drugs because of the possibility of exacerbating this symptom. Tricyclic anti-depressants tend to be anticholinergic – that is, they block the activity of the nerves responsible for gut motion. The long-term consequences of taking low-dose anti-depressants for Irritable Bowel Syndrome are unknown, and this is a matter that should be discussed with your physician.
Narcotic Analgesics for IBS are opioid drugs and can be highly effective painkillers. One of their chief side effects, constipation, is actually of benefit to some Irritable Bowel Syndrome sufferers. Narcotics also induce a feeling of tranquility and promote drowsiness, both of which can be helpful for relieving stress-related attacks. The chief problem with narcotic drugs is that it's next to impossible to get a doctor to prescribe them for you. Although there is mounting evidence that these painkillers are not nearly as habit-forming as previously thought, from your doctor's point of view the risks of addiction are still likely to take precedence over your pain. You'll have to decide for yourself, based on the severity of your symptoms, what your own priorities are in the matter and, if appropriate, try to find an understanding physician.
Narcotic painkillers work best on an empty stomach and may take up to an hour to halt an attack. They should only be used in the advent of severe pain that occurs despite dietary and stress management precautions, and should not be used as a preventative measure or on a regular ongoing basis as they can be addictive. In addition, the less frequently this medication is used the more effective it tends to be.
Drugs For Irritable Bowel Syndrome Diarrhea
Imodium and diphenoxylate/atropine are the most common anti-diarrheal medications for Irritable Bowel Syndrome. They enhance intestinal water absorption, strengthen anal sphincter tone, and decrease intestinal transit, thereby increasing stool consistency and reducing frequency. Both are meant to be used for prevention of diarrhea by taking them prior to events (meals or stress) which typically trigger symptoms. They should be taken with plenty of fresh water. Imodium (loperamide) can be used as a daily maintenance drug, but diphenoxylate/atropine is chemically related to narcotics, and as such is not an innocuous drug, so dosage recommendations should be strictly adhered to (especially in children). diphenoxylate/atropine can be habit-forming, and an overdose could be fatal.
Lotronex, a potent and selective 5-HT3 antagonist that was meant to be prescribed just for women with diarrhea, was pulled off the US market in 2000 after killing several women, and then was re-introduced. It is currently available in the US only under very stringent prescribing restrictions.
Calmactin (cilansetron) is a drug for diarrhea-predominant IBS that was undergoing US clinical trials. However, Calmactin was withdrawn from USA consideration as of 2005 after receiving a "not approvable" action letter from the FDA requesting additional clinical trials. There is no information about future trials currently available.
Drugs For Irritable Bowel Syndrome Constipation
There are no well-established prescription drugs specifically for constipation-predominant IBS. The use of chemical laxatives (such as Milk of Magnesia or ExLax), which tend to stimulate the bowel by causing an irritated lining, is not recommended as they can easily lead to dependency and they're harmful to the colon. The most typical treatment for constipation is a non-prescription soluble fiber supplement, lots of fresh water, and exercise. Unfortunately, this is simply not enough for many people with IBS, but there are currently several research studies underway for a prescription medication that can address the problem safely and effectively.
Amitiza is a prescription medication for the treatment of Irritable Bowel Syndrome constipation in women 18 years of age and older. Amitiza was approved by the FDA for IBS constipation in 2008. Amitiza is classified as a chloride channel activator. Basically, it increases fluid secretion in the intestines, which increases intestinal muscle movement, which helps make it easier to have a bowel movements.
Zelnorm is a drug for Irritable Bowel Syndrome constipation in women, but in 2007 the US FDA requested that Novartis Pharmaceuticals voluntarily discontinue marketing of Zelnorm (tegaserod) based on the finding of an increased risk of serious cardiovascular adverse events (heart problems) associated with use of the drug. Zelnorm had only been approved for prescriptions of short term use.
To learn more about medications as well as non-drug approaches to successfully managing Irritable Bowel Syndrome symptoms, find all you need to know with The First Year: IBS, an essential guide to successfully managing Irritable Bowel Syndrome.
[1] The only critical examination of the efficacy of medical treatments for IBS was conducted in 1988. Measures of efficacy, placebo response, trial length, maintaining blindedness, study designs, and statistical considerations were examined. Of the 93 controlled pharmacologic studies reviewed at the time, not a single study offered convincing evidence that any pharmacologic therapy was effective in treating IBS symptoms. Studies looked at a wide range of pharmacologic interventions including antispasmodics, anticholinergic/barbiturate combinations, antidepressants, bulking agents, dopamine antagonists, carminatives, opioids, tranquilizers, phenytoin, timolol, and diltiazem. This does not mean that pharmacologic interventions do not work, only that no intervention has been proven to be effective. (Klein KB: Controlled treatment trials in the irritable bowel syndrome: a critique. Gastroenterol 1988;95:232-41).
