senna
Black-Draught, Ex-lax Chocolated, Fletcher’s Castoria, Nytilax, Senexon, Senokot, Senolax, X-Prep

Available forms
Available without a prescription
Chewable pieces: 15 mg
Granules: 15 mg/tsp, 20 mg/5 ml
Liquid: 3 mg/ml
Powder: 15 mg/3g
Suppositories: 30 mg
Syrup: 8.8 mg/5 ml
Tablets: 6 mg, 8.6 mg, 15 mg, 17 mg, 25 mg

Indications and dosages
 Acute constipation, preparation for bowel examination. Black-Draught. Adults: 2 tablets or 1/4 to 1/2 level tsp of granules mixed with water. Not for children.
Other preparations
Adults and children age 12 and older: Usual dose is 2 tablets, 1 tsp of granules dissolved in water, or 10 to 15 ml syrup h.s. Maximum dose varies with preparation used.
Children ages 6 to 11: 1 tablet, 1/2 tsp of granules dissolved in water, 1/2 suppository h.s., or 5 to 10 ml syrup. Maximum dose is 2 tablets b.i.d. or 1 tsp of granules b.i.d.
Children ages 2 to 5: 1/2 tablet, or 1/4 tsp of granules dissolved in water. Maximum dose is 1 tablet b.i.d. or 1/2 tsp of granules b.i.d.
Children ages 1 to 5: 2.5 to 5 ml syrup h.s.

Pharmacodynamics
Laxative action: Senna has a local irritant effect on the colon, which promotes peristalsis and bowel evacuation. It also enhances intestinal fluid accumulation, thereby increasing the moisture content of the stool.

Pharmacokinetics
Absorption: Absorbed minimally.
Distribution: May be distributed in bile, saliva and the colonic mucosa, and may appear in breast milk.
Metabolism: Absorbed portion is metabolized in the liver.
Excretion: Unabsorbed senna is excreted mainly in feces; absorbed drug is excreted in urine and feces.

Contraindications and precautions
Contraindicated in patients with ulcerative bowel lesions; nausea, vomiting, abdominal pain, or other symptoms of appendicitis or acute surgical abdomen; fecal impaction; or intestinal obstruction or perforation.

Interactions
None reported.

Adverse reactions
GI: nausea, vomiting, diarrhea, loss of normal bowel function with excessive use, abdominal cramps (especially in severe constipation), malabsorption of nutrients, "cathartic colon" (syndrome resembling ulcerative colitis radiologically) with chronic misuse, possible constipation after catharsis, yellow or yellow-green cast to feces, diarrhea in breast-feeding infants of mothers receiving senna, darkened pigmentation of rectal mucosa with long-term use (usually reversible within 4 to 12 months after stopping drug), laxative dependence with excessive use.
GU: red-pink discoloration in alkaline urine; yellow-brown color to acidic urine.
Metabolic: protein-losing enteropathy, electrolyte imbalance such as hypokalemia.

Effects on lab test results
• May decrease potassium and calcium levels with prolonged use.

Overdose and treatment
No information available.

Special considerations
• Before giving drug, determine if patient has adequate fluid intake, exercise, and diet. Also, stress importance of maintaining these during drug therapy.
• Drug is for short-term treatment.
• In the phenolsulfonphthalein excretion test, senna may turn urine pink to red, red to violet, or red to brown.
• Protect drug from excessive heat or light.
Breast-feeding patients
• Drug appears in breast milk. Diarrhea has been reported in breast-feeding infants.
Pediatric patients
• Senna and other stimulant laxatives are used infrequently in children.
Geriatric patients
• Geriatric patients often overuse laxatives and may be more susceptible to laxative dependency.

Patient education
• Instruct patient that laxative use shouldn’t exceed 1 week. Excessive use may result in dependence or electrolyte imbalance.
• Tell patient that bowel movement may have a yellow or yellow-green cast.
• Teach patient about dietary sources of bulk, including bran and other cereals, fresh fruit, and vegetables.

Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE THREATENING.
◆ Canada only
◇ Unlabeled clinical use