Key takeaways
Lactulose (Constulose) and senna (Senokot, Ex-Lax) are both used to treat constipation, but they work in different ways and have some key differences. Lactulose is an osmotic laxative that draws fluid into the gut to soften stools, and it requires a prescription. It can take up to two days to work and may cause side effects like stomach pain and gas. On the other hand, senna is a stimulant laxative available over-the-counter that works by stimulating the muscles in your intestines. It typically works faster, within 6 to 12 hours, but can cause stomach cramps. Lactulose is generally used for chronic constipation and can be taken long-term under medical supervision, while senna is recommended for occasional use and should not be used for more than a week. Additionally, lactulose is not suitable for people who are lactose intolerant or on a low-galactose diet, whereas senna can be used in children older than 12 and does not have these dietary restrictions.
