Bitter yam
Bitter yam


Bitter yam (Dioscorea dumetorum) is a plant that grows in Africa. Wild forms of the yam can be toxic. Forms grown by farmers generally do not contain toxins.

Bitter yam contains chemicals that might lower blood sugar levels. Wild forms of bitter yam must be soaked and boiled before use to remove the toxins.

People use bitter yam for diabetes and other conditions, but there is no good scientific evidence to support these uses.

Don't confuse bitter yam with wild yam (Dioscorea villosa). These are not the same.
When taken by mouth: Wild, uncooked bitter yam is possibly unsafe. It contains chemicals that can be poisonous and cause seizures. There isn't enough reliable information to know if other forms of bitter yam that are raised by farmers are safe to use as medicine.

Special Precautions & Warnings:

Pregnancy and breast-feeding: There isn't enough reliable information to know if bitter yam is safe to use when pregnant or breast-feeding. Stay on the safe side and avoid use.


There is interest in using bitter yam for a number of purposes, but there isn't enough reliable information to say whether it might be helpful.
Likely effective Effectiveness definitions
Possibly effective Effectiveness definitions
Likely ineffective Effectiveness definitions
Possibly ineffective Effectiveness definitions
Insufficient evidence Effectiveness definitions

Dosing & administration

There isn't enough reliable information to know what an appropriate dose of bitter yam might be. 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 a healthcare professional before using.

Interactions with pharmaceuticals

Digoxin (Lanoxin)

Interaction Rating=Moderate Be cautious with this combination.

Bitter yam may contain chemicals similar to the prescription drug digoxin. Taking bitter yam along with digoxin might increase the risk of side effects.

Interactions with herbs & supplements

Herbs that contain cardiac glycosides: Bitter yam contains chemicals that can affect the heart. These chemicals are called cardiac glycosides. Using it along with other supplements that also contain cardiac glycosides can increase the risk of heart damage. Examples of supplements that contain cardiac glycosides include black hellebore, foxglove, lily-of-the-valley, oleander, and pleurisy root.

Interactions with foods

There are no known interactions with foods. has licensed monographs from TRC Healthcare.
This monograph was last reviewed on 29/06/2023 10:00:00 and last updated on 20/10/2022 07:00:34. Monographs are reviewed and/or updated multiple times per month and at least once per year.
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