Constipation

Introduction

Constipation refers to:

  • Infrequent bowel movements/passing of stool (usually <3 times per week)
  • Difficulty during passing stool or a sensation of hard stools
  • The sensation of incomplete bowel evacuation even after straining

Constipation usually occurs due to inadequate fibre in the diet, lack of proper exercises, defects in the intestines or psychological factors. While the simple causes can be effectively managed with over-the-counter (OTC) medications, long-term constipation needs medical attention to rule out or treat any underlying pathologies. Administration of these medications in children should be only under doctor’s guidance.1–3

OTC Medications

The common OTC medications for constipation have been grouped as follows: 2–5

  • Bulk-forming agents
  • Lubricating agents
  • Stool softeners
  • Osmotic laxatives
  • Stimulants

Bulk-Forming Agents

Bulk-forming agents absorb water and help in the formation of soft, bulky stool, which prompt normal contraction of the muscles of the intestine leading to defecation. Some of these agents along with their trade names are as follows:

  • Methylcellulose (Citrucel)
  • Polycarbophil (FiberCon)
  • Psyllium (Metamucil)

Indications

  • Constipation
  • Long term preventive treatment

Dosage

Oral dose of 15–60 g/day along with at least 8 glasses of water in a day.

Contraindications

  • Allergy to the drug
  • Obstruction in the intestine

Interactions

These agents prevent absorption of medications that are taken within 30 min of the bulk forming agent

Lubricating Agents

These agents tend to lubricate intestine by decreasing the absorption of water from intestine thereby facilitating easy passage of stool.

Some of the drugs under this group are:

  • Glycerin (as a suppository)
  • Mineral oil

Indications

Short term constipation

Dosage

Oral dose of 15–45 mL (mineral oil)

Contraindications

Allergy to the drug.

Interactions

These agents prevent absorption of certain medications such as warfarin, oral contraceptives, and fat-soluble vitamins.

Stool Softeners

The stool softeners also known as emollient laxatives cause addition of water and fat to stool which softens it and allows strain-free movement.

The common drugs are:

  • Docusate sodium (Colace)
  • Docusate calcium (Surfak)

Indications

  • Short-term constipation
  • For individuals with anal fissures or hemorrhoids

Dosage

Oral dose of 50–360 mg/day.

Contraindications

  • Allergy to the drug
  • Short and severe pain in the abdomen
  • Vomiting

Interactions

Prevents absorption of certain medications such as warfarin.

Osmotic Laxatives

These agents cause secretion of water into the intestine by osmosis and thereby soften the stool to ensure its easy passage.

The commonly used drugs and their dosages are as follows:

  • Lactulose: 15–60 mL/day
  • Magnesium citrate:0.5–1 bottle (296 mL)/day
  • Magnesium hydroxide (Milk of Magnesia): 30–60 mL once-daily
  • Polyethylene glycol 3350 (Miralax): Once-daily
  • Sodium biphosphate (Phospho-Soda): 20–45 mL daily
  • Sorbitol: 30–150 mL daily

Indications

Long-term constipated individuals who do not respond to dietary fibre supplementation.

Contraindications

  • Allergy to the drug
  • Decreased or absent urine formation (Sorbitol is contraindicated)
  • Colitis, bowel perforation, gastric retention or bowel obstruction (Miralax)

The osmotic agents should be used carefully in individuals with congestive heart failure and long-term kidney disorders.

Interactions

Prevents absorption of certain medications, which are taken orally.

Stimulants

These agents initiate rhythmic contractions of the muscles of the intestine muscles to eliminate stool.

The common drugs and their dosages are:

  • Bisacodyl (Dulcolax): 5–15 mg daily
  • Cascara sagrada: 5 mL/L tablet once-daily
  • Castor oil: 15–60 mL once-daily
  • Senna (Senokot): 2 or 4 tablets once/twice-daily

Indications

Short-term constipation.

Contraindications

  • Allergy to the drug
  • Vomiting or vomiting sensation
  • Bleeding from the gastrointestinal tract
  • Appendicitis
  • Congestive heart failure
  • Stool impaction

Interactions

Prevents absorption of certain medications, which are taken orally.

When to Seek Medical Help for Constipation

Prompt medical attention should be sought in the following cases:

  • Sudden occurrence of constipation with cramps in the abdomen
  • Severe abdominal pain, especially with the feeling of bloatedness
  • Presence of blood in stool
  • Constipation alternating with diarrhea or associated with vomiting
  • Presence of underlying conditions such as congestive heart failure or kidney disorders
  • Constipation not resolved even after using laxatives for several weeks

References

1.Rao SS. Constipation: evaluation and treatment. Gastroenterol Clin North Am. 2003; 32(2): 659-683.

2.Alonso-Coello P, Mills E, Heels-Ansdell D, Lopez-Yarto M, Zhou Q, Johanson JF, et al. Fiber for the treatment of hemorrhoids complications: A systematic review and meta-analysis. Am J Gastroenterol. 2006; 101(1):181–188.

3.Biggs WS, Dery WH. Evaluation and treatment of constipation in infants and children. Am Fam Physician. 2006; 73: 469–477, 479–480, 481–482.

4.Hsieh C. Treatment of constipation in older adults. Am Fam Physician. 2005; 72: 2277–2285.

5.Schiller LR. Review article: the therapy of constipation. Aliment Pharmacol Ther. 2001; 15: 749–763.

Written by: healthplus24.com team
Date last updated: May 10, 2015