Dear Doctors: I take medication for Type 2 diabetes. I also enjoy horehound candy. I recently ate three candies after taking my medication and experienced a sharp drop in blood sugar. Afterwards, I read that white horehound is attributed to lowering blood sugar. Do you know if this is true?
Dear Reader: White horehound is the common name for a flowering herb in the mint family. Its use as a candy flavoring, and also as a medicinal aide, dates back to ancient Egypt. Often referred to simply as horehound, the botanical name is Marrubium vulgare, a mix of Latin and Hebrew. Vulgare means common in Latin, and Marrubium is believed to derive from the Hebrew words for bitter juice. Botanists suspect the “hore” portion of the name may come from the white fuzz that covers the stems of the plant, which looks like hoarfrost. And just to clear up any possible confusion, there is a plant in the same family known as black horehound. Its botanical name is Ballota nigra. However, it is not the plant you are asking about.
Horehound is quite fragrant, with a pungent and bitter flavor. It is also highly bioactive. Thanks to its complex chemical composition, the herb has antioxidant, anti-inflammatory, expectorant and antimicrobial properties. It has been used to thin mucus secretions in the respiratory tract, stimulate appetite, reduce gas and bloating, manage swelling, ease breathing and help fight off topical and parasitic infections. If you read the labels of cough syrups and lozenges that advertise themselves as an expectorant, you may find horehound in some of the ingredient lists.
More recently, research has begun to look at the possible effects of horehound on blood glucose. A study conducted in 2012 that investigated that question yielded mixed results. But subsequent reviews of the data suggest the herb may, in fact, lead to a drop in blood glucose. The researchers pointed out the inherent difficulties in assessing herbal products, which contain a wide array of bioactive ingredients. They suggested that, by broadening the scope of the analysis of the data, an effect on blood sugar could be seen.
A definitive answer regarding how white horehound may affect blood sugar levels requires further study. However, the initial data, along with a body of anecdotal evidence, suggest that the herb may, indeed, have a hypoglycemic effect. That means people like yourself, who are living with Type 2 diabetes, should be aware of that possibility. Medications for Type 2 diabetes work to lower blood sugar. Using a product that contains white horehound, whether it is a candy or a cough syrup or lozenge, may complicate blood sugar control.
We think it would be wise for you to reach out to your health care provider and tell them of your experience with the horehound candy. If they are not familiar with this potential side effect of the herb, ask them to research it. It is possible you will receive guidance for a safe way to indulge in the treat. But you should also be prepared for the idea that you will have to limit horehound candy, or possibly eliminate it from your diet.
(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)
