From the Guidelines
Senna is a recommended first-line option for individuals with chronic idiopathic constipation due to its efficacy, impact on quality of life, availability over-the-counter, and low cost, as stated in the 2023 American Gastroenterological Association-American College of Gastroenterology clinical practice guideline 1. When using senna, it's essential to consider the dosing, as most commercially available products contain 8–9 mg per tablet, and the dose used in the clinical trial was 1 g by mouth daily for 4 weeks, which is higher than that typically used in clinical practice 1. Some key points to consider when using senna include:
- Typical dose for adults is 8.6-17.2 mg of sennosides taken orally at bedtime, with results usually occurring within 6-12 hours
- Children aged 6-12 should take half the adult dose, while it's not recommended for children under 6 without medical supervision
- Senna works by stimulating the intestinal muscles and increasing water content in the bowels, which helps promote bowel movements
- It should be used short-term (less than 1 week) as prolonged use can lead to dependence, electrolyte imbalances, and weakened bowel function
- Side effects may include abdominal cramps, diarrhea, and discoloration of urine
- Senna should be avoided during pregnancy, by people with inflammatory bowel conditions, intestinal obstruction, or abdominal pain of unknown origin
- For constipation, it's best to first try increasing fiber intake, drinking more water, and physical activity before turning to laxatives like senna Additionally, it's crucial to note that there are no long-term safety studies with senna in humans, and sennosides are not recommended in pregnant women because chemically similar substances have been found to exert weak genotoxic effects in animals, although the supporting evidence is controversial 1. Other options for treating constipation include osmotic laxatives, such as polyethylene glycol (PEG), lactulose, or magnesium and sulfate salts, as well as stimulant laxatives like bisacodyl and sodium picosulfate 1. However, the most recent and highest quality study recommends senna as a first-line option for individuals with chronic idiopathic constipation, making it a preferred choice for treating constipation 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Senna Overview
- Senna is a stimulant laxative commonly used to treat constipation in children and adults 2, 3, 4, 5, 6
- It is available over-the-counter (OTC) and is often used as a first-line treatment for constipation 4, 6
Efficacy and Safety
- Studies have shown that senna is effective in increasing stool frequency and relieving constipation in both children and adults 2, 4, 5, 6
- Senna has been found to be safe when used in appropriate dosages, with common side effects including abdominal cramping, vomiting, and diarrhea 2, 4, 6
- High doses of senna can cause perineal blistering, especially in children, due to prolonged stool-to-skin contact 2
Comparison with Other Laxatives
- Senna has been compared to other laxatives, such as psyllium, and has been found to be more effective in increasing stool frequency and moisture 5
- Polyethylene glycol (PEG) and senna have been found to have good evidence supporting their use as first-line laxatives 4, 6
- Other laxatives, such as fiber supplements, fruits, and magnesium-based products, have moderate evidence supporting their use 4, 6
Recommendations
- Pediatric caregivers should advise families of the rare side effect of skin blistering and educate them to change diapers frequently to reduce stool-to-skin exposure 2
- Senna can be recommended as a safe and effective treatment option for constipation in children and adults, when used in appropriate dosages 2, 3, 4, 6