CONLAX 10 SUPPOSITORY

Indications

• Constipation
• Bowel preparation prior to medical procedures

Dosage

Adults: 5-15 mg orally, taken at bedtime for optimal effect or as directed by a healthcare professional.

Mechanism of action

Bisacodyl is deacetylated to the active metabolite bis-(p-hydroxyphenyl)-pyridyl-2-methane (BHPM) by intestinal deacetylase. BHPM stimulates parasympathetic nerves in the colon, enhancing motility and secretions. It increases cyclic AMP levels by stimulating adenylate cyclase, which leads to active transport of chloride and bicarbonate out of intestinal cells. This process results in passive loss of sodium, potassium, and water. Additionally, bisacodyl decreases aquaporin 3 expression, preventing water reabsorption into the bloodstream and promoting increased water content in the colon, which facilitates stool passage. The drug primarily affects the colonic mucosa, stimulating peristaltic contractions without significantly influencing small intestine motility.

Pharmacodynamics

Bisacodyl has a wide therapeutic index, allowing for doses typically ranging from 5 to 15 mg orally. Patients should be informed about potential side effects, including abdominal pain, nausea, vomiting, and changes in bowel function lasting more than two weeks. It is important to discontinue bisacodyl if rectal bleeding occurs or if there is no bowel movement within 12 hours of administration. The laxative effect is generally seen within 6 to 12 hours after oral dosing.

Pharmacokinetics

Bisacodyl is well absorbed after oral administration and is metabolized in the liver, with the active metabolite exerting its therapeutic effects in the colon. The onset of action typically occurs within 6 to 12 hours when taken orally. The drug is excreted in the urine and feces, and it does not significantly affect the motility of the small intestine.

Contra-indications

• Intestinal obstruction
• Severe dehydration
• Appendicitis
• Acute abdominal conditions

Adverse effects

• Abdominal cramping
• Nausea
• Diarrhea
• Dehydration
• Electrolyte imbalance

Interactions

• May interact with other laxatives, increasing the risk of dehydration and electrolyte imbalance
• Caution with other drugs affecting gastrointestinal motility

Precautions

• Use with caution in patients with severe abdominal pain or nausea
• Avoid prolonged use to prevent dependence
• Monitor for electrolyte disturbances in prolonged use

Pregnancy

Bisacodyl is generally considered safe for use during pregnancy, but should be used under medical advice.

Breast-feeding

Bisacodyl is excreted in breast milk; however, it is considered compatible with breastfeeding when used as directed.

Storage

Store at room temperature, away from moisture and heat. Keep out of reach of children.

Formulations

• Oral tablets (5 mg)
• Suppositories (10 mg)

Mechanism of action

Bisacodyl is deacetylated to the active bis-(p-hydroxyphenyl)-pyridyl-2-methane (BHPM) by an intestinal deacetylase. BHPM can stimulate parasympathetic nerves in the colon directly to increase motility and secretions. Bisacodyl stimulates adenylate cyclase, increasing cyclic AMP, leading to active transport of chloride and bicarbonate out of cells. Sodium ions, potassium ions, and water passively leave the cell; while sodium and chloride ions are unable to be reabsorbed. Water is also be transported from the luminal side of cells into the vasculature by aquaporin 3. Bisacodyl decreases expression of aquaporin 3, preventing water from moving into the vasculature, which may contribute to increased water in the colon. Bisacodyl directly stimulates parasympathetic nerves in the colon, stimulating contraction of longitudinal smooth muscle but not circular smooth muscle. Bisacodyl is a stimulant laxative, ... acting directly on the colonic mucosa-where it stimulates sensory nerve endings to produce parasympathetic reflexes resulting in increased peristaltic contractions of the colon. The contact action of the drug is restricted to the colon, and motility of the small intestine is not appreciably influenced. /Bisacodyl/ increases water retention in the stool by coating surfaces of stool and intestines with a water-immisicible film. Lubricant effect eases passage of contents through intestines. Emulsification of lubricant tends to enhance its ability to soften stool mass. /Laxatives/ Recent studies show that these drugs alter fluid and electrolyte absorption producing net intestinal fluid accumulation and laxation. Some of these drugs may directly stimulate active intestinal ion secretion. Increased concentrations of cyclic 3',5'-adenosine monophosphate (cAMP), occurring in colonic mucosa cells following administration of stimulant laxatives, may alter the permeability of these cells and mediate active ion secretion thereby producing net fluid accumulation and laxative action. /Stimulant Laxatives/ Bisacodyl caused dose-dependent contractions in isolated guinea pig ileum & taenia coli which was not prevented by atropine or pheniramine. It prevented acetylcholine- & histamine-induced contractions. Bisacodyl-induced contractions were not caused by a decrease in endogenous cyclic amp level. However, both endogenous cyclic amp & verapamil (a calcium transport inhibitor) inhibited bisacodyl-induced contractions, suggesting site of action on calcium-dependent contractile system of smooth muscle cells. Intestinal secretagogues as well as the laxative, bisacodyl, raise the K+ efflux rate across the mucosal border by 200-300%. Results suggest that laxatives may increase rate of K+ secretion into the colonic lumen by raising the K+ permeability of the mucosal border.

Pharmacodynamics

Patients should be counselled regarding abdominal pain, nausea, vomiting, or a change in bowel function that lasts longer than 2 weeks. It has a wide therapeutic index, as patients can take 5-15 mg orally. Patients taking bisacodyl should be counselled before taking the medication if they are already experiencing abdominal pain, nausea, vomiting, or a change in bowel function lasting longer than 2 weeks. Patients should also be counselled to stop taking the medication if they experience rectal bleeding or no bowel movement in 12 hours.