Efficacy of Polyethylene Glycol vs Lactulose With Isabgol in Acute Fissure-in-Ano: A Randomized Control Trial (PEGASIS Trial)

Acute fissure in ano is a very common, painful and distressing benign anorectal disorder. It is a linear tear in the anoderm of the distal anal canal most commonly on the posterior midline. They usually result from trauma caused by the passage of hard stool and less commonly from diarrhoea also. The most common presenting symptom is anal pain, bleeding and secondary constipation. Most of the cases are managed conservatively by increasing oral fluid intake, high fibre diet, sitz bath, stool softeners and topical application of sphincter muscle relaxants.

Constipation is one of the most common causes of anal fissure. Patients present to the outpatient department due to acute anal pain resulting from increased internal anal sphincter tone with spasms and hard stool rubbing over the crack. Constipation and pain due to anal fissure are initially managed with lifestyle and dietary modifications like consuming adequate fluids, increased fibre diet and sitz bath.

One of the fibre supplements is isabgol husk, a soluble fibre with enormous water-absorbing properties. Its added benefits include properties like non-irritant to the large bowel, non-fermenting, and dichotomous stool normalising agents, making it one of the most preferred bulk-forming agents. Low cost and over the counter availability are other benefits. Lactulose is also the most commonly prescribed laxative used in acute anal fissures to relieve constipation. Polyethylene glycol is a common osmotic laxative used for the relief of constipation in the treatment of anal fissures.

There are multiple studies that say polyethylene glycol has better efficacy in terms of frequency of stools, and form of stools compared to lactulose or isabgol husk alone. However, there are no studies conducted to compare the efficacy of polyethylene glycol vs combined use of isabgol husk and lactulose in relief of constipation in an acute fissure in ano. However, studies prove that laxatives may reduce/delay the absorption of certain medications, hence medications are advised to be taken 1 hour before or 2-3 hours after taking laxatives.

Patients in both arms will be advised to use local lidocaine with nifedipine cream (Anobliss cream from Samarth Life Sciences Pvt. Ltd., India). One arm will be given polyethylene glycol syrup for 2 weeks maximum and in the other arm, isabgol husk plus lactulose will be given for 2 weeks. Patients will be assessed at the end of a week, and 1 month and evaluated for primary and secondary outcomes.