Senna
Senna is a stimulant laxative from plant anthraquinones, used short term for constipation when softer laxatives have not worked or as your pharmacist or GP advises. It is not usually first choice for long-term daily use without medical review.
This medicine is part of the Stomach acid & reflux category.
Generic name: senna
Quick answers
Short replies to searches people often run before speaking to a clinician. For the overview of what the medicine is used for, see the short summary under the page title above.
What is it for?
Senna is a stimulant laxative from plant anthraquinones, used short term for constipation when softer laxatives have not worked or as your pharmacist or GP advises.
How long does it take to work?
Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review.
What are common side effects?
Stomach cramps, diarrhoea, or nausea.
Can you take paracetamol or ibuprofen with it?
Ask your GP or pharmacist before taking Senna with paracetamol or ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
More about what Senna is used for
Senna is a stimulant laxative from plant anthraquinones, used short term for constipation when softer laxatives have not worked or as your pharmacist or GP advises.
It is not usually first choice for long-term daily use without medical review.
How does Senna work, and how long does it take to work?
It increases bowel contractions and fluid secretion in the colon, often producing a bowel movement within hours to overnight depending on dose.
Brown discolouration of urine can occur harmlessly.
How and when should you take Senna?
Tablets or liquids as the pack directs — often at night for a morning motion. Drink plenty of fluid unless fluid-restricted on medical advice.
Do not exceed maximum duration on packs without GP review.
What are the common side effects of Senna?
Stomach cramps, diarrhoea, or nausea. Prolonged use can lead to lazy bowel dependence in some people.
Serious side effects of Senna — when to get urgent help
Seek urgent help for severe abdominal pain, vomiting, or blood in stool — constipation may be a sign of bowel obstruction.
What if you miss a dose of Senna?
Take the next dose when planned; do not double to catch up.
Who should not take Senna?
Intestinal obstruction, acute surgical abdomen, and severe dehydration need assessment before laxatives.
Pregnancy and breastfeeding need pharmacist or GP advice.
Can you take paracetamol or ibuprofen with Senna? — other interactions
Can reduce absorption of other medicines if gut transit is very fast — separate dosing as advised.
Senna in pregnancy and breastfeeding
Discuss with your midwife or GP before regular use.
Blood tests and monitoring on Senna
If constipation lasts more than a week or keeps returning, see your GP to look for causes.
What might your GP prescribe instead of Senna?
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Frequently asked questions about Senna
People also ask — common Google searches
- What is Senna used for?
- Senna is a stimulant laxative from plant anthraquinones, used short term for constipation when softer laxatives have not worked or as your pharmacist or GP advises. It is not usually first choice for long-term daily use without medical review.
- How long does Senna take to work?
- Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review. Always follow your prescriber’s follow-up plan.
- Can you take Senna with paracetamol or ibuprofen?
- Ask your GP or pharmacist before taking Senna with Paracetamol or Ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
- What are the side effects of Senna?
- Stomach cramps, diarrhoea, or nausea. Prolonged use can lead to lazy bowel dependence in some people. See the sections below for more detail, including serious side effects and when to seek urgent help.
- How long can I take senna?
- OTC packs give a maximum number of days. Longer use should be guided by your GP so dependence and electrolyte problems are avoided.
- Why is my urine brown on senna?
- Harmless colour change is recognised with senna. If urine colour changes worry you or come with pain, seek medical advice.
Need personalised advice?
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