Constipation is a frequently encountered disorder by physicians as well as gastroenterologists. Defining it has been difficult due to variations in bowel habits and perception of bowel habits among different populations. Rather than a definable disease, it is often regarded as a constellation of symptoms that can be described in terms of both the character and frequency of stool. People with constipation can be categorized into two major types: those with difficulty defecating (but normal bowel motion frequency) and those with a transit abnormality (which can present as infrequent defecation).³ Various symptoms reported by patients are reduced bowel motion frequency, excessive straining, passage of hard stools, a sensation of incomplete emptying, a sensation of anal blockage, excessive time spent in unsuccessful defecation or the use of digitation or positioning to aid defecation.

The current review highlights the prevalence of this condition in India and across the world followed by its etiological factors. Subsequently, a section defines the Rome III criteria for the diagnosis of constipation. Lastly, the management of this disorder has been discussed with emphasis on polyethylene glycol (PEG), a valuable laxative for treating patients with constipation.

Medical management of constipation

The treatment of constipation aims at regulating the frequency and quantity of stool to promote successful defecation. Successful defecation can be characterized as sufficient luminal quantity of stool, adequate colonic contractility to evacuate stool toward the anus, and coordinated anorectal movements. The initial management of constipation must involve lifestyle modifications and reassurance of the concept of a healthy or regular bowel movement. Patients should be encouraged to set a regular time for defecation, use proper sitting positions, and monitor their bowel habits by maintaining a diary of the characteristics of their stools. The latter can help evaluate and direct treatment interventions. Besides, medications known to cause constipation should be discontinued or minimized, and metabolic abnormalities like hypothyroidism should be corrected. Patients who need psychological support should be identified and treated as constipation may be aggravated by stress or emotional disturbance.

When nonpharmacologic management fails to improve symptoms, laxatives should be considered. With regard to this, both osmotic and stimulant laxatives are effective, however, long term use of the latter agents must be avoided due to their potential for adverse effects. Furthermore, a vast line of scientific evidence indicates the effectiveness of PEG in patients

PEG, an osmotic laxative is commonly used to manage constipation in adults. It is available in formulations with the addition of electrolytes (PEG+E) or without electrolytes.⁹ PEG 3350 comprises of non-absorbable, non-metabolized polymers of mean molecular weight 3350 (±10%) that act as pure osmotic agents. It contains no more than 0.1% of lower molecular weight PEGs, and are excreted unchanged by glomerular filtration. Therefore, PEG solutions are considered safer than osmotic salts such as magnesium and sodium sulfate or phosphate, especially in patients with impaired renal or cardiac function.

It can be stated that PEG is a truly unique and valuable laxative in the arsenal of treatment options for patients with constipation. In addition, it offers better outcomes than lactulose, especially in terms of stool frequency per week, the form of stool, and the relief of abdominal pain. Therefore, it can be given preference over lactulose for treating constipation.

References

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