Head-to-head comparisons of medication uses, side effects, warnings, and more.
Key takeaways
Senna-S (docusate/senna) and Metamucil (psyllium) are both over-the-counter medications used to treat occasional constipation, but they work in different ways. Senna-S combines a stool softener (docusate) and a stimulant laxative (senna). Docusate draws water into your intestines to soften your stool, while senna stimulates your intestines to help push the stool out. In contrast, Metamucil is a bulk-forming fiber laxative that helps your stool absorb and hold onto water, making it bigger and softer for easier passage. Senna-S typically works within 6 to 12 hours and is often taken at night, while Metamucil can take 12 to 72 hours to relieve constipation and can be taken at any time of the day. Senna-S should be used short-term and can cause stomach cramps and loose stools, whereas Metamucil requires a lot of liquid to prevent choking and can cause bloating. Both medications are available in various forms and do not require a prescription.
Docusate/senna
Psyllium (Metamucil)
Docusate/senna
Psyllium (Metamucil)
Summary of Senexon-s vs. Metamucil
Summary for Stool softener / Stimulant laxative
Docusate/senna is a combination medication containing docusate and senna. The two laxatives work together to treat constipation.
Summary for Fiber laxative
Psyllium or psyllium husk is an over-the-counter (OTC) fiber supplement. It helps with occasional constipation in adults and children. This fiber laxative most often comes as a powder that's mixed with a beverage. But it can also come in capsules that you swallow. You take this laxative by mouth, up to 3 times a day if needed. Some side effects include gas, nausea, and bloating. Metamucil is a common brand name, but there are other brand-name and generic versions.