Bisacodyl

Generic Name

Bisacodyl

Brand Names

Dulcolax

Correctol

Fleet Bisacodyl

Generic preparations widely available as oral tablets or rectal suppositories/enemas

Drug Class

Stimulant laxative

Mechanism of Action

Bisacodyl is a diphenylmethane derivative that stimulates colonic neurons in the myenteric plexus

It increases peristaltic activity of the colon through direct stimulation of enteric nerves

It also alters water and electrolyte secretion, promoting fluid accumulation in the bowel lumen

This leads to bowel evacuation, usually within 6–12 hours orally or within 15–60 minutes rectally

Indications

Approved Uses

Short-term relief of occasional constipation

Bowel cleansing prior to colonoscopy or surgery (as part of bowel prep regimen)

Neurogenic bowel dysfunction (e.g. in spinal cord injury)

Constipation due to medications (e.g. opioids), when fiber or osmotic laxatives fail

Off-label/Investigational Uses

As part of bowel regimen in palliative care

Constipation due to immobility or chronic illness when milder laxatives are insufficient

Formulations and Routes

Oral Tablets (Enteric-Coated)

5 mg per tablet

Swallowed whole with water; do not chew or crush

Onset of action: 6 to 12 hours

Rectal Suppositories

10 mg per suppository

Insert rectally; melt and act locally

Onset: 15 to 60 minutes

Rectal Enema (Bisacodyl enema)

10 mg per 10 mL or 5 mL

Used for rapid evacuation

Onset: 5 to 20 minutes

Dosing and Administration

Adults and Adolescents (≥12 years)

Oral: 5–10 mg once daily before bedtime

Rectal suppository: 10 mg once daily

Rectal enema: 10 mg (single dose)

For bowel preparation: 10–15 mg orally, may be combined with osmotic laxatives or PEG

Children (6–11 years)

Oral: 5 mg once daily

Rectal suppository: 5–10 mg (depending on formulation)

Use only under medical supervision

Children under 6 years

Not routinely recommended

If needed, use only rectal forms with proper pediatric dosage and guidance

Contraindications

Hypersensitivity to bisacodyl or any inactive ingredients

Severe abdominal pain with nausea and vomiting

Intestinal obstruction

Acute surgical abdomen (e.g. appendicitis)

Inflammatory bowel disease in flare (e.g. ulcerative colitis, Crohn's)

Rectal bleeding of unknown cause

Dehydration (especially in children and elderly)

Galactose or lactose intolerance (some tablets contain lactose)

Precautions

Should not be used for more than 5–7 consecutive days without medical supervision

May lead to laxative dependence with chronic use

Caution in elderly due to risk of electrolyte imbalance and dehydration

Avoid in patients with recent GI surgery

Oral tablets must be swallowed whole to prevent gastric irritation

Rectal use may cause local irritation or proctitis if misused

Avoid in patients with anal fissures or hemorrhoids (rectal route) if painful

Adverse Effects

Common

Abdominal cramping

Diarrhea

Nausea

Bloating

Rectal burning or discomfort (suppository/enema)

Less Common

Dehydration

Hypokalemia (especially with chronic or high-dose use)

Dizziness or fainting from fluid loss

Tenesmus (urge to defecate)

Proctitis with chronic rectal use

Rare but Serious

Electrolyte disturbances (hypokalemia, hypocalcemia, hyponatremia)

Metabolic acidosis

Allergic reactions (rash, itching)

Intestinal ischemia (extremely rare and typically due to misuse in bowel prep)

Pregnancy and Lactation

Pregnancy

Oral and rectal forms considered safe for short-term use

Does not appear to cause uterine stimulation

May be used intermittently for constipation during pregnancy when bulk-forming and osmotic laxatives fail

Lactation

Minimal systemic absorption

Considered compatible with breastfeeding

Use in Special Populations

Elderly

More susceptible to dehydration, electrolyte imbalance

Use lowest effective dose

Avoid long-term use

Renal Impairment

Caution with chronic use due to potential electrolyte imbalances

Monitor renal function if used with other nephrotoxic agents

Hepatic Impairment

No dosage adjustment needed

Drug Interactions

Antacids, milk, and PPIs

Can dissolve enteric coating prematurely if taken together

Should be spaced at least 1 hour from bisacodyl tablets

Diuretics (e.g. furosemide, thiazides)

Additive risk of hypokalemia and dehydration

Corticosteroids

May enhance risk of hypokalemia

Cardiac Glycosides (e.g. digoxin)

Hypokalemia may increase sensitivity to digoxin and risk of toxicity

Other Laxatives

Avoid concomitant use unless directed; may lead to additive side effects

Monitoring Parameters

Frequency and quality of bowel movements

Signs of dehydration: dry mouth, thirst, dizziness

Serum electrolytes (especially potassium) in long-term or high-dose use

Rectal irritation in chronic suppository/enema users

Signs of abdominal discomfort that may suggest underlying disease

Patient Counseling Points

Take oral tablets on an empty stomach with a full glass of water

Do not chew, crush, or break the tablets

Avoid taking with antacids, milk, or dairy within 1 hour

Use rectal forms for faster relief when needed

Do not use longer than 5–7 days unless advised by a doctor

Expect mild abdominal cramps; stop use if severe pain or bleeding occurs

Drink plenty of fluids to avoid dehydration

Inform your doctor if constipation persists or worsens

Avoid chronic use to prevent dependence on laxatives

Storage

Store at room temperature

Protect from moisture and heat

Keep out of reach of children and do not share suppositories or enema products