Banaba Leaf Side Effects

Banaba plants are traditionally utilized in the Philippines to treat diabetes. They're high in a natural plant insulin called corosolic acid, and it's the leaf of the plant that contains its medicinal properties. The banaba also may be called crape or crepe myrtle or pride of India. While documented side effects are few, there is little research on the plant and its potential downsides.

Fatigue and Headache

At high dosages, banaba side effects may include fatigue, dizziness and headache, according to "The Health Professional's Guide to Dietary Supplements," by Shawn M. Talbott and Kerry Hughes. The recommended dosage of 8 to 48 mg daily is unlikely to produce such side effects, however.

Hypoglycemia

You'll increase your risk of hypoglycemia, or low blood sugar, if you take banaba along with diabetes drugs including insulin, acarbose, chlorpropamide, glyburide, miglitol, tolazamide and tolbutamide, according to "The Essential Herb-Drug-Medicine Interaction Guide," by George T. Grossberg and Barry Fox. You also increase hypoglycemia risk when you take banaba with other herbs or supplements that lower blood sugar including alpha lipoic acid, psyllium, devil's claw and Panax ginseng. If you are diabetic, your blood sugar levels may fall too low when you take banaba, advise Grossberg and Fox.

Bleeding Risk

There is a theoretical risk of increased bleeding or bruising if banaba is taken along with blood-thinning medications such as aspirin or warfarin. You also need to be cautious and consult a doctor before taking banaba if you have a blood disorder due to this theoretical risk, according to the Integrative Practitioner website.

Pregnancy Concern

Bababa's effects on infants and unborn babies are not well studied, so if you are pregnant or nursing you should avoid banaba, advise the experts at Drugs.com. There is a lack of both pharmacological and toxicity data.