Other Name(s):

Banaba Extract, Banabalean, Corosolic acid, Crape Myrtle, Crepe Myrtle, Extrait de Banaba, Lagerstroemia flos-reginae, Lagerstroemia speciosa, Munchausia speciosa, Myrte de Crêpe, Pride-of-India, Pyinma, Queen's Crape Myrtle.


Banaba is a species of crepe myrtle tree that is native to the Philippines and Southeast Asia. People use the leaves to make medicine.

Banaba is used for diabetes and weight loss.

How does it work?

Banaba seems to lower blood glucose in people with type 2 diabetes, according to very preliminary research. It might help the body use insulin more efficiently.


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Uses & Effectiveness

Insufficient Evidence to Rate Effectiveness for...

  • Diabetes. Some early research suggests that taking a particular banaba extract (Glucosol) for 2 weeks lowers blood sugar by 10% in people with type 2 diabetes. However, other early research suggests that taking a single dose of corosolic acid, a chemical in banaba, before eating does not improve post-meal sugar tolerance.
  • Weight loss.
  • Other conditions.
More evidence is needed to rate the effectiveness of banaba for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

Side Effects

Banaba is POSSIBLY SAFE for most people when taken by mouth on a short-term basis. The long-term safety is unknown.


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Special Precautions & Warnings

Pregnancy and breast-feeding: Not enough is known about the use of banaba during pregnancy and breast-feeding. Stay on the safe side and avoid use.

Diabetes: Banaba can affect blood sugar control, so people with diabetes should monitor their blood glucose levels closely. If you have diabetes, it's best to check with your healthcare provider before starting banaba.

Low blood pressure. Banaba might lower blood pressure. In theory, taking banaba might make blood pressure become too low in people with low blood pressure.

Surgery: Banaba might affect blood sugar levels and could make blood sugar control more difficult during and after surgery. Stop using banaba at least 2 weeks before a scheduled surgery.


Medications for diabetes (Antidiabetes drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Banaba might decrease blood sugar. Diabetes medications are also used to lower blood sugar. Taking banaba along with diabetes medications might cause your blood sugar to go too low. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.

Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.

Medications for high blood pressure (Antihypertensive drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Banaba might decrease blood pressure. Taking banaba along with medications used for lowering high blood pressure might cause your blood pressure to go too low. Do not take too much banaba if you are taking medications for high blood pressure. Some medications for high blood pressure include nifedipine (Adalat, Procardia), verapamil (Calan, Isoptin, Verelan), diltiazem (Cardizem), isradipine (DynaCirc), felodipine (Plendil), amlodipine (Norvasc), and others.

Medications moved by pumps in cells (Organic Anion-Transporting Polypeptide Substrates)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Some medications are moved by pumps in cells. Banaba might change how these pumps work and decrease how much of some medications get absorbed by the body. This could make these medications less effective. Some of these medications that are moved by pumps in cells include bosentan (Tracleer), celiprolol (Celicard, others), etoposide (VePesid), fexofenadine (Allegra), fluoroquinolone antibiotics, glyburide (Micronase, Diabeta), irinotecan (Camptosar), methotrexate, nadolol (Corgard), paclitaxel (Taxol), saquinavir (Fortovase, Invirase), rifampin, statins, talinolol, torsemide (Demadex), troglitazone, and valsartan (Diovan).


The appropriate dose of banaba depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for banaba. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

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