Currently available medicines for IBS


Today, a number of drugs are used for the treatment of IBS symptoms. These drugs are primarily intended for the treatment of various ailments other than IBS, but they are still used because there is a lack of effective medicines available specifically for IBS *. Examples of symptoms that are treated include constipation, diarrhea, pain, gas (balloon stomach). Here we describe some of the registered drugs ** that are currently prescribed as possible treatment options in Sweden for different types of IBS.


This chemical is found in medicines such as Dimor, loperamide Mylan, imodium, lopacut and primodium and is used in the symptomatic treatment of acute nonspecific diarrhea and chronic diarrhea conditions. Loperamide is a synthetic opioid which, however, in therapeutic doses has very little effect on the central nervous system. Loperamide reduces bowel movements and fluid secretion in the intestine but can also make it easier to hold by contracting the muscles in the anal opening. Known side effects include constipation, nausea, flatulence (gas), headache and dizziness.

Cholestyramine is found in medicines such as Questran and Quantalan. Among other things, the drug is approved for the treatment of diarrhea conditions caused by the increased inflow of bile acids in the colon. In the case of so-called bile acid-induced diarrhea, it is recommended that an alternative therapy be initiated unless a response to therapy is obtained within 3 days. Cholestyramine is not absorbed in the gastrointestinal tract but binds bile acids to insoluble complexes. The bile acids can thus not be resorbed but instead, leave the body as feces. Common dose-dependent side effects are constipation.


Karaya gum or Sterculia gum
Sterculia gum is a bulking agent found in the drug Inolaxol. It is approved as an adjuvant in the treatment of both diarrhea and constipation in IBS. An adjuvant is something that can enhance the effect of other treatments. Sterculia is a type of insoluble dietary fiber (cannot be broken down by enzymes or bacteria in the colon), which is extracted from trees in the family Sterculiaceae. Sterculia binds water, which leads to reduced reuptake of water, which in turn gives the intestinal contents an increased volume (the so-called bulking effect). The bulking effect stimulates the bowel movements (peristalsis) and gives the stool a softer consistency. This can normalize bowel function in both hard and loose stools. It often takes time to achieve the full effect of bulking agents. Hypersensitivity reactions and abdominal swelling are side effects that have been reported.

Psyllium or Ispaghula
Psyllium or Ispaghula husk is also a bulking agent found in drugs such as lunelax and Vi-Siblin. Just like sterculia gum, Ispaghula husk is approved as an adjuvant in the treatment of both diarrhea and constipation in IBS. Ispaghula husk consists of the dried so-called epidermis from the mature seeds of Plantago ovata. This binds water, which gives a bulking effect when you eat it, just like sterculia gum. Ispaghula husk however contains potent allergens and even anaphylactic reactions have been reported after use. Skin irritation and a runny nose may also occur. As with other bulking agents, this treatment can also cause stomach problems such as stomach cramps and flatulence.

Bisacodyl is found in medicines such as Dulcolax and Toilax. The active substance bis- (p-hydroxyphenyl) -pyridyl-2-methane (BHPM) is formed only after swallowing bisacodyl which is then reacted with other substances (hydrolysed by esterases) in the intestinal mucosa. The laxative effect comes on average after 6-12 hours. If the medicine is released in the wrong, that is, already in the stomach, you can get stomach pain and the tablets are thus coated with a gastric juice-resistant casing (enteric tablets). The most commonly reported side effects are stomach cramps and diarrhea.

Sodium picosulfate
Sodium picosulfate is found in medicines such as Laxoberal and Cilaxoral. Sodium picosulfate is broken down by bacteria in the colon and can thus affect the mucous membranes in the colon. This increases bowel movements (peristalsis) and increases the amount of fluid in the colon (colon lumen). In other words, medicines with sodium picosulphate speed up the stomach and give a looser and softer stool. The effect occurs after 6-12 hours. Very common side effects are diarrhea and stomach cramps. Abdominal pain and discomfort in the abdomen are also common. Vomiting and nausea are less common but may occur.

Lactulose is found in products such as Duphalac, Lactulose Arrow, Lactulose Meda and more. Lactulose is a synthetic sugar (disaccharide) consisting of the monosaccharides fructose and galactose. The sugar is broken down in the colon by the intestinal bacteria found there. The acids that are then formed, mainly lactic acid, are believed to be able to bind water and thus give a bulking effect (see above). Due to their chemical composition, products with lactulose can often also contain smaller amounts of free lactose and galactose. Common side effects of lactulose are flatulence, abdominal pain, diarrhea and nausea.

Macrogol (Polyethylene glycol)
Macrogol is found in many different drugs such as Forlax, Olopeg, Omnilax, Movicol, Laxido orange, moxalole, Movprep and Laxiriva, as a medication to treat constipation. Several of the drugs also contain potassium chloride. Electrolytes reduce the risk of water, potassium or sodium levels changing. Macrogol has an osmotic effect and increases the flow through the intestinal tract. The most common side effects come from the gastrointestinal tract and consist of, for example, abdominal pain, diarrhea, vomiting, nausea, acid regurgitation, distended abdomen, stomach cramps, flatulence and anal discomfort. Macrogol can also cause headaches and allergic reactions (including anaphylactic shock).

Prucalopride is available as Resolor. Prucalopride is a so-called 5-HT4 serotonin receptor agonist. This means that prucalopride can bind and activate the 5-HT4 receptor on cells in the gastrointestinal tract, which in turn stimulates intestinal motility and thus intestinal emptying. The most commonly reported side effects are headache, abdominal pain, nausea and diarrhea.


  • Antispasmodic
  • Tricyclic
  • Paracetamol
  • Pregabalin


Dimethicone (Simethicone)
Dimethicone (Simethicone) is available in medicines sold under brands such as Minifom, Imodium Plus and Imogaze. Simethicone is a mixture of silica and Poly (dimethylsiloxane) (PDMS). PDMS is a type of silicone oil with defoaming and anti-caking properties that are also used in silicone sealants in the construction sector, in textiles, detergents, cosmetics, lubricating oils, hydraulic fluids and transmission fluid. It is also found in foods, with an E-number, E 900, and occurs in many processed foods such as powdered food, chicken nuggets, beer, jam, juice and frying fat.

PDMS is also sold as a drug such as dimethicone because it can also exert a local effect on the gastrointestinal tract. By reducing surface tension, dimethicone can reduce foaming and cause gas bubbles in the intestine to rupture. Side effects can include nausea, constipation and abdominal pain.

Severe symptoms and in combination with other ailments


SSRIs (Selective Serotonin Reuptake Inhibitors)


Please note that the list is not necessarily complete or in any way a recommended treatment list or the like, but only a compilation of medicines that our readers who suffer from IBS have been prescribed or recommended by their doctors. Examples of medicines are from 2013/2014. Please note that some medicines may have been deregistered or added since this list was updated.

Only your doctor can diagnose and give advice on drug treatment of your ailments! Therefore, contact your care clinic or healthcare counseling for personal information and advice.

* Note that since 2013 there is a registered drug with an approved indication for moderate to severe IBS-C. However, its use is very limited and the risk of side effects is high. Read more about Constella (linaclotide) here.

** There are also some other product categories (not drugs) that are also recommended for IBS. We address these in a separate article. Many times, treatments other than medication can be crucial to help towards learning and managing your IBS symptoms. For example, diet, exercise, and changing routines can work wonders (read more here). Here at you can follow the latest news about IBS.