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Senna Tea: Healthy Natural Laxative or Too Much of a Good Thing?
August 18, 2024
Senna is an herb that comes from a variety of flowering species of Cassia plants, often used to make senna tea.
Senna leaf, fruit and pods have been used in tea form as a purgative or natural laxative for centuries. In fact, Arabian physicians are said to have discussed senna’s medicinal qualities all the way back in 9th century A.D.
Best known as a laxative tea, senna also is approved by the U.S. Food and Drug Administration as a nonprescription laxative.
Can senna help you lose weight? It’s not hard to find senna tea weight loss claims, but it’s typically not recommended as a weight loss aid.
Using laxatives, whether natural or synthetic, to encourage weight loss is not a healthy solution and can be outright dangerous.
Senna is recommended for temporary constipation relief. It’s also employed to clear out the system before certain medical tests like a colonoscopy.
Senna tea is one of the most popular forms of this herbal laxative, but it’s really important not to abuse senna tea or any other senna product.
Learn about the possible benefits as well as the dangers of senna tea below.
What Is Senna Tea?
The senna plant comes in several varieties belonging to the genus Cassia of the pea or legume family (Fabaceae).
Senna plants are native to subtropical and tropical regions like those found in Africa and India. Some wild sennas (Cassia hebecarpa and Cassia marilandica) can also be found growing in the eastern U.S.
Senna leaves, fruit and pods are used to make medicinal products like senna tea and senna supplements. Senna tea most often comes from two senna plants: Cassia acutifolia or Cassia angustifolia.
Is senna a laxative or a stool softener? It is considered a laxative, which by definition means it is a medicine or agent for relieving constipation.
As a laxative, senna can stimulate intestinal contractions that lead to a bowel movement. These contractions are caused by active chemical components in senna called anthraquinone glycosides known as sennosides.
Senna is only effective as a laxative if its sennosides are transformed into rheinanthrones by beneficial bacteria in the colon.
What are the side effects of senna? The most common potential side effects are gastrointestinal upset, but these can often be avoided by not taking more than a recommended dose and not using any senna product for longer than a week at a time.
Uses
1. Constipation relief
Constipation, a very common health concern, is definitely a top reason why people choose to try this herbal remedy.
Senna tea is approved by the FDA as a nonprescription laxative. How can it help?
Senna has been shown in controlled trials to soften stools while also increasing stool frequency and weight.
How long does it take for a senna laxative to work? On average, it takes about eight hours, but it can commonly take anywhere between six and 12 hours.
A common recommendation is to have senna tea before bedtime to have constipation relief the next morning. As a natural constipation remedy, it can be used as a temporary form of relief but should not be a long-term solution.
2. Hemorrhoids treatment
Hemorrhoids are swollen veins in the anus and lower rectum. They can often be the result of constipation and straining to pass a bowel movement.
Hemorrhoids can be quite uncomfortable and unpleasant so many people look for natural ways to relieve hemorrhoids.
Since senna tea can help make constipation and straining less likely, it makes sense why some people choose senna tea to help avoid and recover from hemorrhoids. In fact, it’s been shown to help in treating anal lacerations and hemorrhoids in studies.
3. Irritable bowel syndrome (IBS) help
Some of the most common IBS symptoms include changes to bowel movements, such as diarrhea or constipation. When constipation is a problem, sometimes stimulant laxatives like senna may be recommended.
Senna is at times prescribed by conventional doctors when lactulose does not relieve constipation.
More scientific studies are warranted to support the use of senna for IBS symptoms. If you have IBS, do not use senna without speaking to your doctor first.
4. Colonoscopy prep
Senna tea is sometimes recommended as a way to cleanse the colon prior to undergoing a colonoscopy.
What is a colonoscopy? It’s a medical procedure to look at the inside of the colon, also known as the large intestine, which is the last part of the digestive system.
Before having this procedure, the colon needs to be completely clear of accumulated waste. Taking senna by mouth has been shown to be as effective as castor oil and conventional products like bisocodyl (Dulcolax) for bowel preparation before a colonoscopy.
Risks, Side Effects and Interactions
Senna is a nonprescription medicine approved by the FDA. It is generally considered safe when taken by mouth by most adults and children over the age of two on a short-term basis.
What are the side effects of drinking senna tea? General senna side effects may include:
- stomach discomfort
- cramps
- diarrhea
- nausea
- vomiting
- bloating
- fluid loss
- abdominal pain
- electrolyte disturbances
- feeling faint
Senna is considered to be possibly unsafe if you take it in high doses or long term. It is not recommended to take senna in any form for longer than one to two weeks at a time.
When used long term, senna warnings include abnormal bowel function and laxative dependence. Using senna long term may also alter electrolyte balance, which can lead to muscle weakness, disordered heart function, damage to the liver damage and other serious, unwanted senna side effects.
It’s wise to discontinue use of senna laxative products if you develop diarrhea or watery stools.
Some severe symptoms and side effects of senna may include:
- liver injury
- changes in heart rhythms
- electrolyte disturbances
- jaundice
- encephalopathy
- dark or brown urine
- weakness
- ab pain
Is senna tea during pregnancy and breastfeeding use safe? Check with your doctor first, but typically the herb is considered likely to be safe if it’s taken by mouth and only used on a short-term basis.
As long as it’s used as directed, senna doesn’t seem to result in stool changes in babies of nursing moms.
It is important to note that senna tea can lead to laxative dependence and liver damage when it is not used properly. Improper use includes using senna tea or any other senna product in high doses, long term or too frequently.
Senna should not be used by anyone experiencing any of the following:
- an electrolyte disturbance, such as a potassium deficiency
- dehydration
- diarrhea or loose/watery stools
Speak with your doctor before using senna, if you have a heart condition or a gastrointestinal condition, including abdominal pain (diagnosed or undiagnosed), intestinal blockage, Crohn’s disease, ulcerative colitis, irritable bowel syndrome, appendicitis, stomach inflammation, anal prolapse or hemorrhoids.
For anyone with the following health issues, senna should not be used unless instructed otherwise by your doctor:
- intestinal obstruction
- heart disease
- ulcerative colitis
- diarrhea
- Crohn’s disease
- dehydration
- appendicitis
- kidney problems
- abdominal pain
- allergy to senna
- conditions that cause intestinal obstruction
There are a few known senna drug interactions. Senna may interact with the following drugs: digoxin (Lanoxin), warfarin (Coumadin), diuretic drugs (water pillows) and contraceptive drugs.
People who take the following should be careful about possible interactions with senna:
- hear rhythm meds
- blood thinners
- licorice root
- diuretics
- steroids
- contraceptives
- digoxin
- warfarin
- estrogens
In terms of interactions with other herbs/supplements, there is concern that senna should not be combined with horsetail or licorice since this may increase the chance that potassium levels in the body go too low.
Urine can take on a red-brown color while taking senna. This is typically considered harmless, and color should return to normal after you stop taking senna.
Again, please remember that senna is not a long-term solution for constipation. Using senna for too long can actually stop your bowels from working properly on their own.
It is rare but possible to have an allergic reaction to senna. Seek emergency medical care if you think you are having a serious allergic reaction to senna.
A very rare yet serious possible senna side effect is to have a severely raised, red, itchy skin rash on any part or all of your body.
Comparisons
Senna tea vs. castor oil
Like senna, castor oil is a natural substance taken by mouth for constipation relief. Both senna and castor oil are natural laxatives that can help prevent straining during defecation and also help with a sense of complete evacuation after a bowel movement.
Castor oil generally works quicker than senna products. While senna may take six to 12 hours to work, castor oil is known to work in as little as two hours or up to six hours after ingesting it.
While senna tea can be taken before bedtime to produce a bowel movement the following morning, castor oil works so fast that it’s not recommended before bedtime.
Like senna tea, castor oil may cause cramping or diarrhea. In addition, castor oil is known to possibly lead to feelings of nausea.
Castor oil is rich and thick so it can be harder to get down than senna tea.
Pregnant women should not take this oil without speaking with their doctors first since it may induce labor.
Senna tea and castor are both considered stimulant laxatives and should not be taken long term since long-term use or overuse can lead to more health problems.
Senna tea vs. sencha green tea
Senna sounds a lot like sencha tea, but senna is an herbal tea while sencha is a type of green tea.
Senna tea tastes slightly sweet but also has strong bitter undertones so some people like to mix it with green tea. Senna tea does not contain caffeine while green tea does contain caffeine (in lesser amounts than black tea but more than white tea).
As you can see from the section above, senna tea’s benefits are quite focused on the digestive system, most specifically on clearing out the colon. Green tea has a much more varied array of possible benefits, including reduced risk of some types of cancer, type II diabetes and heart disease.
While it’s not recommended to use senna tea for weight loss, green tea can be a healthy daily beverage to boost weight loss efforts. Scientific research has linked the catechins, a natural component of green tea, to reduced body fat, weight loss and prevention of obesity.
Green tea can safely be consumed my most people on a daily basis, and even multiple cups a day long term are typically not problematic. The same cannot be said for senna tea, which should only be used for short-term periods, and no more than one cup per day is typically recommended.
How to Make
If you’re wondering where to buy senna tea, it can be easily found at your local health food store or online. Meanwhile, senna laxative supplements come in a variety of forms, including as a tea, liquid, powder or tablet.
You can buy senna tea bags, or you can make senna tea yourself from dried senna.
You can purchase either senna leaves or senna pods for use as a laxative tea. Senna pods are said to have more mild effects than the senna leaf.
How to make senna tea from dried unprocessed senna is very easy.
Simply combine one to two teaspoons of senna with one cup of boiled water. Let the senna tea steep for 10 minutes.
The longer the tea sits, the stronger it gets, and you definitely want to avoid making the tea too strong. This is why some people prefer other senna supplements where the dose of senna is more standardized.
Other teas like chamomile or peppermint are sometimes added to senna tea to make the taste more pleasant and also to decrease the likelihood of gas or cramping.
Senna Supplement (Dosage)
How long does senna tea take to work? Senna usually begins to work within six to 12 hours after drinking senna tea or taking a supplement by mouth. Time can vary by product.
Senna leaf tea and other senna supplements are commonly taken before bed to encourage a bowel movement the following morning.
The strength of senna tea can be affected by brew time so one challenge with senna tea is that the dosage is harder to control compared to a supplement. Senna teas also vary by maker so the amount of senna can be different in senna tea bags, and many brands also combine other stimulant laxative herbs, such as cascara, into their products.
It can be helpful to read senna tea reviews before choosing the product that’s best for your needs.
Dosing (by mouth) which has been studied in scientific research:
- For constipation in adults and children age 12 and over: Usual dose is 17.2 milligrams daily, not to exceed 34.4 milligrams per day.
- For constipation in children over two but under 12: 8.5 milligrams daily increased just enough to cause one bowel movement daily.
- For constipation in elderly people: 17 milligrams daily.
- For constipation following pregnancy: 28 milligrams in two divided doses.
Senna tea dosage: Typically just one cup of senna tea per day is recommended to alleviate constipation, but it should not be taken for longer than one week unless directed by a doctor.
Is there a difference between senna and Senokot? Yes, Senokot is a senna medication that in addition to sennosides also contains docusate.
Is Senokot a laxative or stool softener? It’s actually both because the sennna-derived sennosides have laxative effects while the docusate is considered a stool softener.
Final Thoughts
- What is senna? Senna is an herb known to be a natural laxative that has been used medicinally for centuries.
- Is senna a good laxative? Yes, it can be, but it should never be a replacement for healthy habits like drinking enough water every day, eating a diet rich in healthy fiber and getting plenty of regular exercise.
- To be on the safe side and avoid unwanted side effects, you shouldn’t drink more than one cup of senna tea a day, and do not use senna products for more than one week at a time.
- Senna tea is known to help naturally relieve constipation and clear out the bowels before a colonoscopy. Sometimes, senna is recommended in cases of hemorrhoids and IBS with constipation, but speak with your doctor first.
- The dangers of abusing senna tea or any senna product are extremely serious and should not be taken lightly. Using senna long term may also alter electrolyte balance, which can lead to muscle weakness, disordered heart function and liver damage.