Because little is known about the causes of IBS, most medications are directed at managing the symptoms of IBS. However, the FDA has recently approved a few medications to treat the causes behind specific cases of IBS.
The first line of treatment for IBS patients is most often symptom management through lifestyle and dietary changes. These include:
Restricted diet. Patients may be asked to cut out inflammatory food groups or change the balance of their diet.
- High-gas foods such as cabbage, broccoli, and carbonated beverages should be avoided by those who suffer from gas and abdominal bloating.
- FODMAPs (fermentable oligo-, di-, and monosaccharides and polyols) are a certain type of carbohydrate that causes gut irritation in many IBS sufferers. FODMAPs can be found in fruits such as apples, mangoes, vegetables such as cabbage and onion, and grain products such as breakfast cereals and wheat noodles.
- Gluten is a point of controversy among those treating IBS patients. Some believe that it has inflammatory effects in the bowel while others do not. There has not been sufficient scientific research done to produce conclusive data.
Exercise regimen. Exercise can help minimize stress and promote regular digestion. If you do not already exercise regularly, your doctor may suggest implementing a routine that is manageable for you.
Nutritional Supplements. If the bowels are moving too quickly, proper nutrient absorption may be disrupted, leading to critical nutrient deficiencies such as iron deficiency and vitamin B deficiency. Ask your doctor or a registered dietitian about what supplements are best for you.
Medications. Medications are also available to help manage IBS symptoms. These include:
- Laxatives can help treat symptoms of constipation. Though laxatives are available over the counter, patients with IBS should consult with a doctor before using them as they might worsen IBS symptoms.
- Bulking agents can help to coagulate stool and ease stool passage. Examples include bran or psyllium husk.
- Anticholinergics/Antispasmodics have limited benefit for treating IBS. In some persons they relieve abdominal pain or discomfort, usually if the symptoms occur soon after eating. Examples include:
- Dicyclomine (Bentyl)
- Hyoscyamine (Levsin).
- Anti-anxiety and anti-depressant medications – Since the mind and gut are so closely related, medications that treat chemical imbalances in the brain that affect mood may help relieve symptoms of IBS when given in smaller doses. Many anti-anxiety and anti-depressant medications have serious side effects. Consult with your doctor about the possible risks and benefits of each medication. Anti-anxiety and anti-depressant medications used to treat IBS include:
- Amitriptyline
- Bupropion (Wellbutrin)
- Citalopram (Celexa)
- Desipramine (Norpramin)
- Fluoxetine (Prozac)
- Imipramine (Tofranil)
- Paroxetine (Paxil)
- Sertraline (Zoloft)
- Trazodone
- Venlafaxine (Effexor)
If symptoms worsen while taking any of these medications, or thoughts of suicide develop, stop taking the medication immediately. If you are experiencing thoughts of suicide, call the suicide hotline at 1-800-273-TALK (8255)
The following are the FDA approved medications for the treatment of IBS:
Alosetron (Lotronex). Alosetron has been linked to serious side effects, and prescription of the medication is therefore limited to female patients suffering from IBS with diarrhea who have not responded to other treatments. Alosetron works by relaxing the colon and lengthening the time it takes stool to pass through the colon.
Common side effects of Alosteron include:
- Stomach pain
- Nausea
- Constipation
More serious side effects include:
- Severe constipation
- Ischemic colitis (blocked blood flow to the colon)
- Fever
- Rapid heart rate
Do NOT take Alosteron if you:
- Suffer from constipation or IBS with constipation
- Have a history of blood clots
- Have suffered from bowel blockage
- Have evidence of blocked blood flow to the colon (ischemic colon)
- Have suffered or currently suffer from Crohn’s disease, ulcerative colitis, diverticulitis, or liver disease.
- Are taking fluvoxamine (Luvox)
Lubiprostone (Amitiza). Lubiprostone is also connected to serious side effects, and is therefore limited to female patients 18 years and older suffering from IBS with constipation who have not responded to other treatments. Lubiprostone works by increasing the secretion of fluids in the small intestine to help ease the passing of stool.
Common side effects of Lubiprostone include:
- Nausea
- Diarrhea
- Abdominal pain and distension
More serious side effects include:
- Severe diarrhea
- Severe nausea
- Chest tightness
Do NOT take Lubiprostone if you:
- Have severe diarrhea
- Have liver disease
Lubiprostone may cause fetal harm, though studies are inconclusive. If you are pregnant or are thinking about getting pregnant, consult with your doctors about before taking Lubiprostone.
Linaclotide (Linzess). Linaclotide was approved for the treatment of IBS with constipation for both men and women in 2012. Linaclotide works by increasing the movement of food and waste through the gastrointestinal tract and by blocking problematic nerve signals in the colon.
Common side effects include:
- Diarrhea
- Gas
- Abdominal bloating
- Abdominal pain
More serious side effects include:
- Severe diarrhea
- Bloody stools