Rhubarb is a plant. The root and underground stem (rhizome) are used to make medicine.
Rhubarb is used primarily for digestive complaints including constipation, diarrhea, heartburn, stomach pain, gastrointestinal (GI) bleeding, and preparation for certain GI diagnostic procedures. Some people use rhubarb so they have to strain less during bowel movements; this reduces pain from hemorrhoids or tears in the skin lining the anal canal (anal fissures).
Rhubarb is sometimes applied to the skin to treat cold sores.
In food, rhubarb stems are eaten in pie and other recipes. Rhubarb is also used as a flavoring agent.
How does it work?
Rhubarb contains several chemicals which might help heal cold sores.
Possibly Effective for:
- Stomach bleeding. Taking rhubarb by mouth as a powder or extract seems to help treat stomach bleeding.
- Cold sores. Applying rhubarb along with sage to herpes cold sores seems to improve healing. It might be as effective as acyclovir (Zovirax) cream.
- Kidney failure. Most research suggests that taking rhubarb extract, with or without captopril, improves kidney function in people with kidney failure.
- Constipation. Early research suggests that taking rhubarb and Glauber’s salt mixture improves constipation.
- Gum disease. Early research suggests that rinsing with a rhubarb extract can help treat gum disease.
- Kidney disease (glomerulonephritis). Early research suggests that taking a combination of 10 herbs including rhubarb daily for 3 months might improve kidney function in people with glomerulonephritis.
- Gonorrhea. Early research suggests that taking tablets that contain rhubarb extract might reduce symptoms of gonorrhea.
- High cholesterol. Early research suggests that taking rhubarb, alone or with water plantain, can reduce total cholesterol and low-density lipoprotein (LDL or “bad”) cholesterol in people with high cholesterol.
- Cancer affecting the area behind the nose (nasopharyngeal cancer). Early research suggests that taking a specific product containing rhubarb and other herbs (Shenlong) along with radiation therapy does not improve healing in people with nasopharyngeal cancer.
- Non-alcoholic fatty liver disease. Early research suggests that taking a specific Chinese herbal medicine containing rhubarb, giant knotweed, dried green orange peel, and dried old orange peel (Danning Pian) might improve liver function in people with non-alcoholic fatty liver disease.
- Obesity. Some early research suggests that taking rhubarb extract 1-3 times daily for up to 3 months might reduce body weight in obese people. However, other research shows that taking rhubarb with other herbs does not reduce weight.
- High blood pressure during pregnancy. Early research shows that taking rhubarb extract daily starting 28 weeks into pregnancy and continuing until delivery can reduce the risk of high blood pressure during pregnancy.
- Life-threatening infection (sepsis). Early research suggests that taking rhubarb powder along with standard treatments might help cure and reduce the risk of death from a life-threatening infection called sepsis.
- Recovery after surgery. Early research suggests that adding rhubarb to intravenous (IV) nutrition in people undergoing surgery for stomach cancer can improve recovery.
- Stomach pain.
- Other conditions.
Side Effects & Safety
Rhubarb is LIKELY SAFE when the root is consumed as food. It is POSSIBLY SAFE for most adults when taken by mouth in medicinal amounts for up to 3 months.
Rhubarb can cause some side effects such as stomach and intestinal pain, watery diarrhea, and uterine contractions. Long-term use can result in muscular weakness, bone loss, potassium loss, and irregular heart rhythm.
There is a report of kidney failure in someone who took a product containing rhubarb. But it’s not known for sure if rhubarb was the actual cause of kidney failure.
Special Precautions & Warnings:Children: Rhubarb is POSSIBLY UNSAFE for children. There is one report of a 4-year-old who ate rhubarb leaves and died. Rhubarb leaves contain a lot of oxalic acid, which can be deadly if taken in large enough doses. Because of their small size, children are at highest risk for oxalic poisoning after eating rhubarb leaves.
Pregnancy and breast-feeding: Rhubarb is POSSIBLY UNSAFE when used in amounts greater than those found in foods.
Diarrhea or constipation: Rhubarb can make diarrhea or constipation worse, depending on the preparation used.
Gastrointestinal (GI) conditions: Don’t take rhubarb if you have a bowel obstruction; appendicitis; unexplained stomach pain; or inflammatory conditions of the intestines including Crohn's disease, colitis, and irritable bowel syndrome (IBS).
Kidney disease: There is a chemical in rhubarb that might harm the kidneys. In fact, a supplement that contained rhubarb has been linked to one report of kidney failure. If you already have kidney disease, don’t risk making it worse by taking rhubarb.
Kidney stones: Rhubarb contains a chemical that the body can convert into kidney stones. If you have ever had kidney stones, don’t take rhubarb.
Liver problems: Rhubarb can make liver function worse in people who already have liver problems. People who have liver problems should avoid rhubarb.
Moderate Interaction Be cautious with this combination
- Digoxin (Lanoxin) interacts with RHUBARB
Rhubarb is a type of laxative called a stimulant laxative. Stimulant laxatives can decrease potassium levels in the body. Low potassium levels can increase the risk of side effects of digoxin (Lanoxin).
- Medications for inflammation (Corticosteroids) interacts with RHUBARB
Some medications for inflammation can decrease potassium in the body. Rhubarb is a type of laxative that might also decrease potassium in the body. Taking rhubarb along with some medications for inflammation might decrease potassium in the body too much.
Some medications for inflammation include dexamethasone (Decadron), hydrocortisone (Cortef), methylprednisolone (Medrol), prednisone (Deltasone), and others.
- Medications taken by mouth (Oral drugs) interacts with RHUBARB
Rhubarb is a laxative. Laxatives can decrease how much medicine your body absorbs. Decreasing how much medicine your body absorbs can decrease the effectiveness of your medication.
- Medications that can harm the kidneys (Nephrotoxic Drugs) interacts with RHUBARB
Taking rhubarb might harm the kidneys in some people. Some medications can also harm the kidneys. Taking rhubarb with medications that can harm the kidneys might increase the chance of kidney damage.
Some of these medications that can harm the kidneys include cyclosporine (Neoral, Sandimmune); aminoglycosides including amikacin (Amikin), gentamicin (Garamycin, Gentak, others), and tobramycin (Nebcin, others); nonsteroidal anti-inflammatory drugs (NSAIDs) including ibuprofen (Advil, Motrin, Nuprin, others), indomethacin (Indocin), naproxen (Aleve, Anaprox, Naprelan, Naprosyn), piroxicam (Feldene); and numerous others.
- Stimulant laxatives interacts with RHUBARB
Rhubarb is a type of laxative called a stimulant laxative. Stimulant laxatives speed up the bowels. Taking rhubarb along with other stimulant laxatives could speed up the bowels too much and cause dehydration and low minerals in the body.
Some stimulant laxatives include bisacodyl (Correctol, Dulcolax), cascara, castor oil (Purge), senna (Senokot), and others.
- Warfarin (Coumadin) interacts with RHUBARB
Rhubarb can work as a laxative. In some people rhubarb can cause diarrhea. Diarrhea can increase the effects of warfarin and increase the risk of bleeding. If you take warfarin do not to take excessive amounts of rhubarb.
- Water pills (Diuretic drugs) interacts with RHUBARB
Rhubarb is a laxative. Some laxatives can decrease potassium in the body. "Water pills" can also decrease potassium in the body. Taking rhubarb along with "water pills" might decrease potassium in the body too much.
Some "water pills" that can decrease potassium include chlorothiazide (Diuril), chlorthalidone (Thalitone), furosemide (Lasix), hydrochlorothiazide (HCTZ, HydroDiuril, Microzide), and others.
The following doses have been studied in scientific research:
APPLIED TO THE SKIN:
- For treatment of cold sores: a cream containing 23 mg/gram each of rhubarb extract and sage extract applied every 2 to 4 hours while awake, with treatment starting within one day of symptom appearance and continuing for 10 to 14 days.