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Laxatives Explained: Stimulant Laxatives – Part 4

Updated: Oct 12, 2021

Senokot, Dulcolax and constipation

Stimulant Laxatives


Senokot, which contains the active ingredient senna, is a stimulant laxative. Senna works by irritating the intestinal walls causing motility (movement) of the intestine and by accelerating the movement of waste through the large intestine. It also influences the secretions in the large intestine by inhibiting absorption and by increasing the leakiness of the intestinal walls which causes secretion of water and electrolytes. The additional water in the large intestine softens stools, and due to the increase in the contents in the large intestine, it causes an increase in defecation.

Stimulant laxatives should not be used long term due to their effect on the leakiness of the intestinal wall and irritation of the intestinal wall. Furthermore, stimulant laxatives can cause dependency.

Dose: The recommended dose is one or two tablets to be taken at night before bed. It is recommended to start with the lowest dose (one tablet). Senna should only be used for a maximum of one week. A bowel movement would be expected 8-12 hours after taking the dose.


This is also a stimulant laxative. It works by stimulating your bowels to contract and by promoting the accumulation of water and electrolytes in the bowel. This causes peristalsis of the bowel (bowel movement) and softening of the stools. Stimulant laxatives irritate the wall of the intestines which causes it to contract and therefore helping to stimulate the movement required to propel waste along, thus usually reducing constipation. However, as it irritates the wall of the intestine, these should be for only be used occasionally as they can damage the function of the intestine. As well as this, the accumulation of water and electrolytes in the bowel can cause dehydration and electrolyte imbalances and long term use should be avoided. Stimulant laxatives can also have the unwanted side effect of producing diarrhoea and an urgency to go to the bathroom.

Dose: The recommended dose is one or two tablets to be taken at night before bed. It is recommended to start with the lowest dose (one tablet). You should expect a bowel movement the next morning. Once regular bowel movements are established the dose should be stopped.

Colon Hydrotherapy compared to Stimulant Laxatives

Colon hydrotherapy copies the action of stimulant laxatives by stimulating the intestinal walls to contract, thus helping to remove waste. However, it does not irritate the intestinal walls. Colon hydrotherapy uses water which creates a small pressure against the bowel wall and therefore causing it to contract against the water to push it along. This is similar to the natural action that faeces would have against the wall, which similarly causes the intestines to contract and propel waste along. Unlike stimulant laxatives, colon hydrotherapy does not cause the bowel to become lazy and reliant on it. It actually exercises the intestinal muscles and therefore can cause them to become better functioning after treatment.


What you can see from the “Laxatives Explained” series is that colon hydrotherapy works similar to each of the laxatives, however without the unwanted side effects such as bloating, gas, diarrhoea, abdominal pains, electrolyte imbalances, irritation of the intestinal wall and dependency. As well as this, colonics can give immediate relief which not many of the laxatives can give.

Colonics have the additional benefit of exercising the intestinal wall which can aid it in performing better post treatment. Colonics can help clear the intestines of impacted or hard stools and thus can act as a body reset.

There are almost no side effects from colonics, and most people leave feeling lighter, brighter, relaxed and more energised.

If you are suffering from constipation or finding yourself buying laxatives more frequently than you would like, book in today and see how much better you could feel. What have you got to lose!


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