Brand names: Black Draught, Dr. Caldwell, Dr. Edwards’ Olive, Evac-U-Gen, Ex-Lax, ... show all 9 brands Fletcher’s, Perdiem, Senexon, Senokot
Drug class: Cathartics and Laxatives
ATC class: A06AB06
VA class: GA204
CAS number: 8013-11-4

Medically reviewed by Drugs.com on Oct 2, 2023. Written by ASHP.

Introduction

Stimulant laxative; hydroxymethylanthraquinone derivative occurring naturally in plants as glycosides.

Uses for Senna

Constipation

Used to relieve occasional constipation.

Mildest of the stimulant laxatives; less pronounced laxative effect than bisacodyl or the violent purgation produced by castor oil.

Use of stimulant laxatives for simple constipation is seldom necessary or desirable.

If a stimulant laxative is used, senna derivatives may be preferred.

Used to treat constipation that occurs following prolonged bed rest or hospitalization.

Has been used to treat constipation during pregnancy or the puerperium; bulk-forming laxatives or stool softeners preferred.

Because senna may be distributed into milk, other laxatives usually are preferred for postpartum constipation.

Also has been used to treat constipation resulting from diminished colonic motor response in geriatric patients but, because this type of constipation frequently is due to psychological or physical laxative dependence, bulk-forming laxatives preferred.

Used to treat constipation occurring secondary to idiopathic slowing of transit time, to constipating drugs, or to irritable bowel or spastic colon syndrome.

Also has been used to treat constipation in patients with neurologic constipation.

Colonic Evacuation

Used orally to empty the bowel prior to surgery or radiologic, proctoscopic, or endoscopic (e.g., sigmoidoscopic, proctoscopic) procedures.

Usually supplemented with administration of rectal evacuants (e.g., saline, stimulant, or soapsuds enemas) immediately before radiologic procedures.

Related/similar drugs

MiraLAX, erythromycin, lactulose, docusate, Colace, bisacodyl, polyethylene glycol 3350

Senna Dosage and Administration

Administration

Oral Administration

Administer orally, in conjunction with adequate fluid intake.

May be administered 1–2 times daily; however, usually administered as a single dose at bedtime.

Oral Solution

Shake well before use.

Tablets

Swallow tablets with a glass of water; do not crush, break, or chew.

Chewable Tablets or Pieces

Chew tablets or allow to dissolve in mouth before swallowing.

Chew piece(s) before swallowing.

Dosage

Available as sennosides, standardized senna concentrate, and standardized senna fruit extract; dosage expressed in terms of sennosides.

Administer as infrequently as possible at the lowest effective dosage level. Do not use for >1 week unless directed by prescriber.

Senna fluidextract: 33.3 mg/mL senna concentrate contains 3 mg sennosides A & B per mL.

Pediatric Patients

Constipation

Stimulant laxatives generally avoided in children <6 years of age.

Oral (Standardized Senna Concentrate)

Children 2–6 years of age: 4.3 mg once daily; maximum 8.6 mg twice daily.

Children 6–11 years of age: Usually, 8.6–15 mg 1–2 times daily. May increase to a maximum 17.2 mg twice daily.

Alternatively, for children 6–11 years of age: 25 mg (1 maximum strength tablet) 1–2 times daily.

Alternatively, for children ≥6 years of age: 10 mg as chewable tablet 1–2 times daily.

Children ≥12 years of age: Usually, 17.2–30 mg 1–2 times daily. May increase to a maximum 34.4 mg twice daily.

Alternatively, for children ≥12 years of age: 50 mg (2 maximum strength tablets) 1–2 times daily.

Oral (Senna Fluidextract Oral Solution)

Children 2–5 years of age: 15–30 mg (5–10 mL) 1–2 times daily. Do not give concentrate containing alcohol to children <6 years of age unless otherwise directed by prescriber.

Children 6–15 years of age: 30–45 mg (10–15 mL) 1–2 times daily.

Children ≥12 years of age: Alternatively, 45–90 mg (15–30 mL) of oral solution (with alcohol) may be administered before or after meals or at bedtime. May repeat in 6–8 hours if needed.

Oral (Standardized Senna Fruit Extract Oral Solution)

Children 2–5 years of age: 4.4–6.6 mg (2.5–3.75 mL) once daily. May increase to a maximum 6.6 mg (3.75 mL) twice daily.

Children 6–11 years of age: 8.8–13.2 mg (5–7.5 mL) 1–2 times daily. May increase to a maximum 13.2 mg (7.5 mL) twice daily.

Children ≥12 years of age: 17.6–26.4 mg (10–15 mL) once daily. May increase to a maximum 26.4 mg (15 mL) twice daily.

Oral (Sennosides and Docusate Fixed Combination)

Children 2–5 years of age: 4.3 mg of sennosides and 25 mg of docusate sodium once daily. May increase to a maximum 8.6 mg of sennosides and 50 mg of docusate sodium twice daily.

Children 6–11 years of age: 8.6 mg of sennosides and 50 mg of docusate sodium once daily. May increase to a maximum 17.2 mg of sennosides and 100 mg of docusate sodium twice daily.

Children ≥12 years of age: 17.2 mg of sennosides and 100 mg of docusate sodium once daily. May increase to a maximum 34.4 mg of sennosides and 200 mg of docusate sodium twice daily.

Adults

Constipation

Oral (Standardized Senna Concentrate)

Usually, 17.2–30 mg 1–2 times daily. May increase to a maximum 34.4 mg twice daily.

Alternatively, 50 mg (2 maximum strength tablets) 1–2 times daily.

Oral (Senna Fluidextract Oral Solution)

45–90 mg (15–30 mL) before or after meals or at bedtime. May repeat in 6–8 hours if needed.

Oral (Standardized Senna Fruit Extract Oral Solution)

17.6–26.4 mg (10–15 mL) once daily. May increase to a maximum 26.4 mg (15 mL) twice daily.

Oral (Sennosides and Docusate Fixed Combination)

17.2 mg of sennosides and 100 mg of docusate sodium once daily. May increase to a maximum 34.4 mg of sennosides and 200 mg of docusate sodium twice daily.

Colonic Evacuation

To prepare for colonic surgery or radiologic, sigmoidoscopic, or proctoscopic procedures, patient should receive a residue-free diet 1 day before the surgery or procedure. Castor oil may be administered 16 hours before surgery or procedure; and a cleansing rectal enema (e.g., tap water, soap suds, saline laxative, bisacodyl tannex enema) administered on the day of surgery or procedure.

Oral (Standardized Senna Fruit Extract or Standardized Senna Concentrate)

105–157.5 mg as a single dose 12–14 hours before surgery or procedure.

Prescribing Limits

Pediatric Patients

Constipation

Do not use for >1 week unless directed by prescriber.

Oral (Standardized Senna Concentrate)

Children 2–6 years of age: Maximum 8.6 mg twice daily.

Children 6–11 years of age: Maximum 17.2 mg twice daily.

Alternatively, for children 6–11 years of age: Maximum 25 mg (1 maximum strength tablet) 2 times daily.

Children ≥12 years of age: Maximum 34.4 mg twice daily.

Alternatively, for children ≥12 years of age: 50 mg (2 maximum strength tablets) 2 times daily.

Oral (Standardized Senna Fruit Extract Oral Solution)

Children ≥12 years of age: Maximum 26.4 mg (15 mL) twice daily.

Oral (Sennosides and Docusate Fixed Combination)

Children 2–5 years of age: Maximum 8.6 mg of sennosides and 50 mg of docusate sodium twice daily.

Children 6–11 years of age: Maximum 17.2 mg of sennosides and 100 mg of docusate sodium twice daily.

Children ≥12 years of age: Maximum 34.4 mg of sennosides and 200 mg of docusate sodium twice daily.

Adults

Constipation

Do not use for >1 week unless directed by prescriber.

Oral (Standardized Senna Concentrate)

Maximum 34.4 mg twice daily.

Oral (Standardized Senna Fruit Extract Oral Solution)

Maximum 26.4 mg (15 mL) twice daily.

Oral (Sennosides and Docusate Fixed Combination)

Maximum 34.4 mg of sennosides and 200 mg of docusate sodium twice daily.

Special Populations

No special population dosage recommendations at this time.

Cautions for Senna

Contraindications

• Acute abdominal pain, nausea, vomiting, or other symptoms of appendicitis or undiagnosed abdominal pain.

• Intestinal obstruction.

Warnings/Precautions

Warnings

Chronic Use or Overdosage of Laxatives

Chronic use or overdosage of laxatives may produce persistent diarrhea, hypokalemia, loss of essential nutritional factors, and dehydration.

Electrolyte disturbances (including hypokalemia, hypocalcemia, metabolic acidosis or alkalosis), abdominal pain, diarrhea, malabsorption, weight loss, and protein-losing enteropathy may occur.

Electrolyte disturbances may produce vomiting and muscle weakness; rarely, osteomalacia, secondary aldosteronism, and tetany.

Chronic use may cause pathologic changes including structural damage to the myenteric plexus, severe and permanent interference with colonic motility, and hypertrophy of the muscularis mucosae.

“Cathartic colon” with atony and dilation of the colon, especially of the right side, has occurred with habitual use (often for several years); often resembles ulcerative colitis.

Change in Bowel Habits

If a sudden change in bowel habits occurs that last >2 weeks, consult a clinician before using.

General Precautions

Discoloration of Urine and Colonic Mucosa

May discolor colonic mucosa (melanosis coli); innocuous and reversible.

May discolor urine pink to red or brown to black.

Diabetes Mellitus

Standardized senna fruit extract contains large amounts of sugar; consider caloric value in patients with diabetes mellitus.

Use of Fixed Combinations

When senna is used in fixed combination with docusate sodium, consider the cautions, precautions, and contraindications associated with docusate sodium.

Specific Populations

Pregnancy

Category C.

Lactation

May be distributed into milk. Unlikely to appear in sufficient amounts to affect nursing infants.

AAP considers senna compatible with breast-feeding.

Pediatric Use

Safety and efficacy not established in children <2 years of age. Avoid use of laxatives in infants and children.

Common Adverse Effects

Abdominal discomfort, nausea, mild cramps, griping, faintness.

Drug Interactions

GI Drug Absorption

By increasing intestinal motility, can potentially decrease transit time of concomitantly administered oral drugs and thereby decrease their absorption.

Specific Drugs and Laboratory Tests

Senna Pharmacokinetics

Absorption

Bioavailability

Minimal absorption following oral administration.

Onset

Following oral administration, laxation usually occurs within 6–12 hours; may take 24 hours.

Distribution

Extent

Distribution not fully characterized; may be distributed into bile, saliva, and colonic mucosa.

Elimination

Metabolism

Absorbed drug metabolized in the liver.

Elimination Route

Absorbed drug and its metabolites eliminated in feces via biliary excretion and/or in urine.

Stability

Storage

Oral

Tablets and Chewable Pieces

20–25°C (may be exposed to 15–30°C); protect from moisture.

Solution

Tight, light-resistant container at ≤40°C.

Actions

• Stimulant laxative; primary active cathartic principles are the stereoisomeric glucosides, sennosides A and B.

• Precise mechanism of action not known.

• Commonly thought that the stimulant laxatives induce defecation by stimulating propulsive peristaltic activity of the intestine through local irritation of the mucosa or through a more selective action on the intramural nerve plexus of intestinal smooth muscle, thus increasing motility.

• More recent evidence shows that stimulant laxatives alter fluid and electrolyte absorption, producing net intestinal fluid accumulation and laxation.

• Increases concentrations of cyclic 3′,5′-adenosine monophosphate (cAMP) in colonic mucosal cells and may alter the permeability of these cells and mediate active ion secretion, producing net fluid accumulation and laxative action.

• Mainly promotes evacuation of the colon.

Advice to Patients

• Importance of informing clinicians before use if abdominal pain, nausea, or vomiting is present or if there has been a sudden change in bowel habits that persists over a period of 2 weeks.

• Importance of discontinuing use and informing clinician if a bowel movement does not occur or rectal bleeding occurs after use.

• Importance of not using laxative products for a period longer than 1 week unless directed by a clinician.

• Importance of taking with a glass of water.

• Advise about risk of laxative abuse and potential serious consequences. (See Chronic Use or Overdosage under Cautions.)

• Importance of advising clinicians of preexisting diabetes mellitus since some preparations contain sugar (e.g., standardized senna fruit extract).

• Advise patients of a potential discoloration in urine.

• Importance of taking 2 hours before or 2 hours after taking other medications.

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses, including intestinal obstruction.

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.

• Importance of informing patients of other important precautionary information. (See Cautions.)

Additional Information

The American Society of Health-System Pharmacists, Inc. represents that the information provided in the accompanying monograph was formulated with a reasonable standard of care, and in conformity with professional standards in the field. Readers are advised that decisions regarding use of drugs are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and that the information contained in the monograph is provided for informational purposes only. The manufacturer’s labeling should be consulted for more detailed information. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information contained in the monograph is not a substitute for medical care.

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

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Frequently asked questions

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