Senna Dosage and Administration for Constipation

Adult Dosing Guidelines

• The American Gastroenterological Association recommends a typical starting dose of 8.6-17.2 mg daily (equivalent to 1-2 standard tablets) for tablet formulations of senna 1
• In palliative care settings, the National Comprehensive Cancer Network recommends senna may be dosed at 2-3 tablets twice to three times daily for patients with severe constipation 2

Mechanism of Action and Efficacy

• Senna contains anthranoid plant compounds that are hydrolyzed by colonic bacteria to yield active molecules, and has both motor and secretory effects on the colon, stimulating peristalsis 3
• The American Gastroenterological Association reports that in clinical trials, senna significantly increased complete spontaneous bowel movements compared to placebo 4

Clinical Considerations

• The American Gastroenterological Association recommends senna for short-term use (4 weeks or less) or as rescue therapy 5
• While long-term use is probably appropriate in some cases, data on tolerance and side effects with extended use are limited, according to the American Gastroenterological Association 5, 4
• The American Gastroenterological Association suggests starting at a lower dose and increasing if there is inadequate response 4

Side Effects and Precautions

• Common side effects of senna include abdominal pain, cramping, and diarrhea, particularly at higher doses, according to the American Gastroenterological Association 4
• Stimulant laxatives like senna may be too strong for overtly weak or debilitated patients, as reported in the Annals of Oncology 3

Practical Administration Tips

• For patients with cancer-related constipation, the National Comprehensive Cancer Network recommends senna may be increased to 2-3 tablets BID-TID with the goal of one non-forced bowel movement every 1-2 days 2
• The National Comprehensive Cancer Network suggests considering adding other laxatives if constipation persists despite optimal senna dosing 2