Senna (Black Draught, Fletcher’s Castoria, Gentlax)


  • Gastrointestinal


  • Stimulant laxative


  • Constipation

  • Bowel evacuation or preparation for surgery or examination


  • GI bleeding, obstruction, fecal impaction, abdominal pain, nausea or vomiting

  • Symptoms of appendicitis, acute surgical abdomen


  • Pregnancy category C; not excreted into breast milk; compatible with breast feeding

  • Fluid and electrolyte imbalance can occur with abuse

  • Abuse, dependency

  • Children

Adverse Reactions (Side Effects):

  • GI: anorexia, cramps, diarrhea, nausea, vomiting

  • METAB: alkalosis, enteropathy, hypocalcemia, hypokalemia, tetany


Administered orally (tablet, granules, syrup), rectally

  • Adult:   

    • PO up to 1600mg daily; tablets (187-600mg), 1-8 tablets daily; granules (163-1600mg per ½ teaspoonful), ¼ to ½ teaspoonful daily; syrup (218 mg/5ml), 5-20ml daily; 

    • PR up to 1600mg daily; suppository (650mg) 1-2 daily

  • Child >6years; >27 kg: Do not use Black Draught (granules) for children; 

    • PO up to 800mg daily; tablets (187-600mg), 1-4 tablets daily; syrup (218 mg/5ml), 10-30ml daily;

  • Child 2-5 years: 

    • PO up to 300-400mg daily

  • Child 1 month to 1 year: 

    • PO up to 300-400mg daily; syrup 1.25-5ml daily

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