Constipation Treatment & Management

Manual disimpaction and transrectal enemas may be used after any critical illness associated with constipation has been ruled out. A well-lubricated gloved finger might be required in patients with lower anorectal impactions. Warm water enemas usually are unpopular among the nursing staff and probably are not necessary within the emergency department (ED). These initial measures are then followed by elective evaluation of the causes of the constipation.

Medical care should focus on dietary change and exercise rather than laxatives, enemas, and suppositories, none of which really address the underlying problem. The patient is at high risk for becoming dependent on laxatives and developing a laxative colon. If conservative measures fail and the patient is clearly compliant with the advice, a more detailed evaluation should be performed (see Workup).

The key to treating most patients with constipation is correction of dietary deficiencies. Although some controversy exists about the effectiveness of exercise in constipation treatment, encouraging as much aerobic exercise as possible seems reasonable. Even brisk walking may help stimulate bowel motility and, certainly, is unlikely to hurt most patients.

Counsel the patient regarding the appropriate dietary prophylaxis with follow-up visits on an outpatient basis. If the patient experiences further episodes of constipation, a more detailed evaluation may then become appropriate (see Workup).

Surgical care is generally restricted to the evaluation of underlying causes or the management of acute complications of constipation. Surgical intervention for constipation should be avoided in a patient with an underlying psychiatric cause.

Once acute constipation has resolved and the associated medical or surgical conditions have been ruled out, additional inpatient care is rarely indicated. Patients requiring surgical intervention for acute conditions require postoperative care; however, that is beyond the scope of this article.

Generally, transfer is not required unless that there is uncertainty about the diagnosis or the underlying cause and more aggressive medical evaluation is deemed necessary. Such an eventuality might occur in patients institutionalized in nursing homes or in chronic care facilities who require medical consultations to rule out conditions that are more serious. The following factors may warrant a transfer:

• Uncertain diagnosis
• Evidence of intra-abdominal catastrophe
• Acute abdominal pain
• Fever
• Lower gastrointestinal (GI) bleeding
• Chills
• Instability of vital signs
• Absence of bowel sounds
• Acute recent change in bowel habits
• Unsuccessful or inadequate treatment offered at the local facility

The key to treating most patients with constipation is correction of dietary deficiencies. This generally involves increasing intake of fiber and fluid and decreasing the use of constipating agents, such as milk products, coffee, tea, and alcohol.

Increased fiber intake

Dietary fiber is available in diverse natural sources, such as fruits, vegetables, and cereals. Ingestion of natural fiber sources is nutritionally superior to supplementation with purified fiber. However, advising patients to eat more fruits and vegetables is frequently unsuccessful, at least in American patients. American patients do respond reasonably well to prescriptions and often seek them; accordingly, prescribing a fiber supplement, such as wheat, psyllium, or methylcellulose, is often useful.

Many of the available products vary substantially in their potency. For instance, sugar-free Metamucil (psyllium) has twice the potency of standard Metamucil on a volume basis because the latter is half sugar. Pharmaceutical companies may argue that one type of fiber is better tolerated or more effective than another. This may not make much difference in treatment or in fiber tolerance in most patients as long as the fiber supplementation doses start low and are slowly titrated upward.

Theoretical considerations suggest that the use of a fermentable fiber, which increases short-chain fatty acid concentrations in the colonic lumen, may have other health benefits (as opposed to methylcellulose). However, this suggestion remains controversial and awaits further exploration.

Because no convincing reason exists to pick one product over another, a single brand of choice should be prescribed until the patient’s constipation resolves. The patient may then switch to generic or other brands with appropriate dose adjustments.

The author’s experience has been that some patients have preferences based on the taste of the product or other subjective reasons. In particular, those rare patients who cannot tolerate fermentable fiber supplementation because of resulting gas or bloating may do better with methylcellulose, whereas others may find that the quality of the stool, taste preferences, or both favor psyllium supplementation.

To prevent patient noncompliance resulting from the cramping and bloating that may accompany changes in dietary fiber, fiber supplementation should be started at a low subtherapeutic dose and titrated upwards on a weekly basis until the desired effect is achieved. Patients should continue to increase the dose on a weekly basis until they experience daily bowel movements with no straining or until they reach the maximum dose.

Patients should be cautioned that these products are not laxatives, will not induce a bowel movement, and must be taken daily regardless of their perceived need.

Patients may increase or decrease their dose on a week-to-week basis. In particular, the author advises patients who have arrived at what they believe to be an appropriate and successful dose to increase the dose 1 additional step for at least a week and then back down if they wish. Some patients find that they actually prefer the higher dose. To ensure long-term compliance, the author believes that patients should titrate the doses in case of changes in potency between fiber supplement brands or changes in diet, fluid intake, or exercise.

Patients should be cautioned that, although various stool softeners, such as docusate sodium, appear much more palatable than fiber, they are not suitable for long-term use. Tachyphylaxis to stool softeners develops over time.

Increased fluid intake

Fluid intake is the key to treatment. Patients should be advised to drink at least 8 glasses of water daily. Counseling may be required to achieve this goal.

Milk and milk products should be minimized if these prove constipating.

In some patient populations, coffee, tea, and alcohol account for the majority of the fluid volume consumed. Patients should be made to understand that because of the diuretic effects of these products, this state of affairs is counterproductive. The author usually recommends that patients decrease their consumption of coffee, tea, and alcohol as much as possible and that they make a point of consuming an extra glass of water for every drink of coffee, tea, or alcohol.

Failure of high-fiber, high-water regimen

Failure to control constipation on a regimen of fiber supplementation and increased water intake should prompt an analysis of patient compliance and a search for other physical causes (eg, altered colonic transit time, outlet obstruction, and psychological causes). The author’s experience is that early failures usually reflect inadequate water intake, whereas recidivism months to years later usually reflects a patient’s decision that fiber supplementation is no longer necessary. Counsel patients in advance to encourage them to avoid these inappropriate decisions.

In selected patients who comply with a trial of a high-fiber, high-water diet but find that this approach does not successfully treat their constipation, a trial of a very-low-residue diet, or even a liquid diet, may be appropriate.

Such a regimen is most successful in patients with outlet obstruction who are not candidates for surgical correction and in patients whose presentation is more characteristic of IBS with a chief complaint of abdominal pain. A low-residue diet may be effective in the latter group of patients if thorough mechanical cleansing of the bowel, such as is done for diagnostic endoscopy or barium enema, temporarily relieves their symptoms.

Medications to treat constipation include bulk-forming agents (fibers), emollient stool softeners, rapidly acting lubricants, prokinetics, laxatives, osmotic agents, and prosecretory drugs.

Fiber is arguably the best and least expensive medication for long-term treatment, although enthusiasm for the use of polyethylene glycol as first-line therapy in chronic constipation is increasing. It is important to convey to patients that bulk-forming agents generally do not work rapidly and must be used on a long-term basis.

Emollient stool softeners are easier to use, but they lose their effectiveness with long-term administration. These drugs are best used for prophylaxis in a short-term setting, as in patients receiving a postoperative narcotic prescription.

Rapidly acting lubricants and laxatives, including over-the-counter products, are often used to treat acute and chronic constipation. A meta-analysis affirmed the efficacy of bisacodyl and sodium picosulfate, which share the same active metabolite, in short- to medium-term use in chronic idiopathic constipation.^[12] However, their use for acute episodes should be limited, because of the long-term risk of habituation or toxicity.

Polyethylene glycol is simple to use and is more effective than placebo in the management of chronic constipation; however, the effects of long-term therapy with polyethylene glycol over decades are still not well studied.

Newer therapies for constipation include prucalopride, a prokinetic selective 5-hydroxytryptamine-4 (5-HT4) receptor antagonist that stimulates colonic motility and decreases transit time, and the osmotic agents lubiprostone and linaclotide,^[13] which stimulate intestinal fluid secretion by acting on the intestinal epithelial chloride channel and the guanylate cyclase receptor, respectively.

These drugs may be useful in chronic constipation when fiber, water, and polyethylene glycol fail, either alone in combination with simpler interventions. When moving a patient to such interventions after failing on fiber, water, and polyethylene glycol, reconsider whether mechanical issues (eg, tumors, pelvic floor problems) have been adequately ruled out.

Other drugs that have been studied include the prokinetic agents cisapride and tegaserod.^{[14, 15]} Although significant promise had been shown with this new class of drugs, these 2 agents were withdrawn from the US market.

As of July 27, 2007, restricted use of tegaserod is permitted via a treatment investigational new drug (IND) protocol.^[16] The treatment IND protocol allows tegaserod treatment of irritable bowel syndrome (IBS) with constipation (IBS-C) or chronic idiopathic constipation (CIC) in women younger than 55 years who meet specific guidelines. Its use is further restricted to those in critical need who have no known or preexisting heart disease.

Renzapride, a mixed 5-HT4 receptor agonist and 5-HT3 receptor antagonist, has been tested to assess its efficacy and safety in the treatment of chronic constipation.^[17]

Neurotrophin-3 stimulates the development, growth, and function of the nervous system and has been used to treat functional constipation. Stem cells have been suggested as a means of repopulating dysfunctional neurons.

Surgical care is generally restricted to the evaluation of underlying causes, such as large bowel obstruction, volvulus, or intra-abdominal infection or ischemia. Surgical care may also be indicated for the management of acute complications of constipation, such as hemorrhoidal thrombosis.

Surgery may occasionally play a role in the management of rectal outlet obstruction (eg, rectocele, rectal prolapse, internal rectal intussusception) or in patients with a hypomotile (laxative) colon who are refractory to medical treatment.

In the former case, treatment is directed at the cause of the outlet obstruction. In the latter case, total abdominal colectomy may be indicated; the operation may be less morbid if performed laparoscopically.^{[18, 19]} In both cases, thorough preoperative evaluation is essential to rule out other medically treatable causes or potentiating factors.

These patients may also have an underlying psychological cause for their ailment, and addressing this is important before irreversible surgical interventions are contemplated.

Benign outlet obstruction due to prolapse may be managed by means of stapled transanal rectal resection or anopexy.^{[20, 21]} Laparoscopic ventral rectopexy has also been advocated for this problem, although this may be more invasive.^[22]

There is increasing interest in the use of sacral nerve stimulation in carefully selected patients with severe refractory constipation. In such patients, temporary percutaneous stimulation is typically used for 2-3 weeks to seek benefit, but such trials may not always predict success with permanently implanted nerve stimulators.^{[23, 24]} This technology seems promising, but further experience will be required to clarify its indications, risks, and benefits.

Pregnant women

Pregnant women are frequently constipated because of dietary alterations, anatomic impingement of a large uterus on the rectosigmoid, fluid shifts, decreased exercise levels, and reduced mobility. Typically, these women develop hemorrhoids from passive venous congestion and uterine impingement. Pregnancy-related constipation potentiates the development of symptomatic hemorrhoids, and the resolution of constipation is the only available antihemorrhoidal therapy during pregnancy.

First-line treatment is fiber supplementation, increased water intake, gentle exercise, and occasional laxative use as required. Hemorrhoidal suppositories and sitz baths may offer symptomatic relief.

Attentive management is particularly important to minimize acute and subacute hemorrhoidal complications induced by the straining associated with vaginal delivery.

Elderly persons

Elderly patients appear to be particularly prone to constipation. The rate of self-reported constipation rapidly increases in patients older than 65 years. Careful review of prescribed medications may reveal 1 or more agents that may potentiate constipation.

Manipulating their diets and encouraging patients to exercise are the cornerstones of treatment. Laxatives may be required, particularly in patients with a history of chronic laxative abuse.

Children

Constipation is frequently diet-related in children, particularly in toddlers who are being switched from formula feeds to milk. Small children are especially liable to experience constipation that is more prolonged. This is associated with painful bowel movements caused by an acute anal fissure, which forces the child to avoid bowel movements.^[25]

Painful defecation produces a vicious positive feedback cycle in these children. The child suppresses the urge to defecate, and this results in the formation of a larger and harder stool. When the stools eventually emerge, the pain of defecation is worse, encouraging the child to retain the stools further.

Prescribing long-term laxatives for a period of several weeks may be necessary in order to force the child to defecate daily until the cause of the anorectal pain is resolved and the fecal retention behavior is unlearned. Once this pattern has been unlearned, usually within several weeks, laxatives should be gradually tapered off while the use of fiber and fluid supplementation should indefinitely continue. Failure to taper the laxatives without the return of constipation indicates the need for a gastroenterologic consultation to rule out an underlying problem.

The first-line therapy remains dietary manipulation, with increased fluid intake and increased ingestion of fiber, whether via natural sources such as fruits and vegetables or via supplements containing more purified forms of fiber (eg, wheat germ, psyllium, methylcellulose, and malted barley extract). These may be mixed with liquids and administered with the help of a child’s feeding bottle. Stool softeners and local care of any anal fissures may be helpful.

Mentally incapacitated individuals

In mentally incapacitated patients with a pattern of bowel retention, resolution of this pattern requires aggressive short-term use of laxatives, stool softeners, and local care of any anal fissures. As with children, once this pattern has been unlearned, laxatives should be gradually tapered off while fiber and fluid supplementation continues indefinitely. If the laxatives cannot be tapered without constipation returning, a gastroenterologic consultation is required to rule out an underlying problem.

Surgical consultation is indicated when large bowel obstruction or colonic ileus secondary to an acute intra-abdominal process is suspected. It is also indicated for anorectal complications of constipation or for surgical correction of the underlying cause. Symptomatic hemorrhoids and anal fissures represent complications of constipation until proven otherwise. Acute hemorrhoidal thrombosis requires urgent surgical consultation for evacuation of the clot and relief of pain.

For prolonged chronic hemorrhoids, a trial of aggressive medical treatment (fiber supplementation, increased water intake, exercise, decreased coffee and alcohol intake, sitz baths, and local symptomatic treatment) should be carried out before surgical consultation.

Similarly, acute anal fissures should be managed conservatively because most respond well to aggressive programs of sitz baths, stool softeners, and local anesthetic ointment.

Chronic nonhealing fissures may be managed with topical nitroglycerin or botulinum toxin injections with reasonable success. However, the long-term recurrence rate after such therapy has yet to be established. Many of these patients may require surgical sphincterotomy. Uncontrolled anal dilation has become less popular than sphincterotomy because of concerns over an increased risk of sphincter injury. A colorectal surgeon should be consulted for patients with chronic fissures to evaluate the need for surgical intervention and to consider biopsy of the fissure to rule out malignancy.

Perirectal abscess and fistula in ano may be related to chronic constipation. These complications do not respond to medical management and require surgical referral.

A consultation with a gastroenterologist is necessary to rule out other colonic processes and to assist with the long-term program of stool softener and laxative use in patients who do not respond to simple measures.

Either a gastroenterologist or a surgeon may be consulted for lower GI endoscopy, depending on local referral patterns and the availability of expertise, or (in adults) to differentiate benign solitary rectal ulcers from rectal malignancy.

A psychological or psychiatric consultation may be appropriate before surgical intervention to treat patients with potential or identified psychological issues.

After constipation resolves in a patient who was acutely constipated, outpatient care requires the following measures:

• Confirming that the patient is not chronically constipated
• Ruling out colorectal pathology

For a patient who is chronically constipated, outpatient care may include the following:

• Colonic imaging or endoscopic visualization
• Dietary management
• If these measures fail in a compliant patient, further evaluation