What is Senna?
Senna is a laxative treatment made from the leaves and fruit of the senna plant. It is used to treat difficulty passing stools, a condition more commonly known as constipation.
What is Senna used for?
The treatment is used for the short-term relief of occasional constipation, when other measures have failed. If experiencing constipation, the first recommendation is to try diet and lifestyle measures, such as increasing fluid and fibre intake and increasing physical activitity such as a daily walk or run. If this fails, a bulk-forming laxative such as Fybogel or an osmotic laxative such as Movicol or Laxido is recommended as first line treatment. Following this, if your bowel motions are soft but still difficult to pass, a stimulant laxative such as senna may be used for short- term relief.
How does Senna work?
When Senna is broken down in the digestive tract, the byproducts it leaves irritate the colonic wall. This stimulates the bowel and helps stools move through the digestive tract more easily.
How long does Senna take to work?
The treatment takes around eight hours to work, but may be longer depending on how severe your constipation is.
How should I take Senna?
Because it takes eight hours for the treatment to work, Senna is best taken at night. Adults and children aged 12 and above should take one to two tablets at bedtime. Children under this age should see a GP if experiencing constipation.
It’s important to drink lots of water during the day while taking Senna. You should aim to drink six to eight glasses a day, or your constipation may get worse.
Do not take Senna for longer than two weeks. Using the treatment for long periods of time can stop your bowel working properly on its own, and cause harm and side effects. If your constipation persists, you should consult with your GP.
Who can’t take Senna?
Senna isn’t suitable for everyone. Women who are pregnant or breastfeeding should consult their GP before using Senna because the effects may pass on to the baby. In most cases, doctors will prescribe laxatives that don’t get absorbed by the gut for pregnant women.
There are also some medicines that may interact badly with Senna. You must consult your GP before using Senna if you’re taking:
- Heart medications such as digoxin or quinidine
- A diuretic
- Steroid tablets
- Liquorice root preparations
What are the side effects of Senna?
Side effects are common with Senna, but these are usually very mild. They include:
- Stomach cramps
- Red-brown urine (this is normal and will go away when your treatment ends)
In very rare cases, Senna can sometimes cause a severe rash to form on any part or all of your body. If this happens, you should stop taking Senna and seek immediate medical help.
Does Senna help with weight loss?
Stimulant laxatives such as Senna do not aid weight loss and should not be used for this purpose. For further information about how to manage your weight safely, you should consult your GP.
How should I store Senna?
Senna should be stored in a dry, cool environment that does not exceed 25°C.
Always read the patient information leaflet before commencing treatment.
Important: We advise you to always read the patient information leaflet inside the medication box, as the generic medication may not always entirely match the patient information leaflet listed. Please contact us if you have any questions.
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Content last updated: 02 Feb 2023