October 18, 2023

Ensuring safety with taking supplements and herbals during cancer treatment

Open bottle with supplement tablets spilled out in front of it

UW Health | Carbone Cancer Center’s oncology pharmacists are a helpful resource for patients considering taking supplements or practicing herbal medicine during their cancer treatments.

Clinical pharmacists Elizabeth Dow-Hillgartner and Maggie Schenkat said that whether those substances are beneficial depend on the unique factors of each patient’s diagnosis and treatment plan, which is why having these conversations with medical professionals is so important.

“I think at the end of the day, we always look at these from a safety standpoint for patients, taking into consideration their cancer, their treatments, what stage of treatment, is it a curative intent or quality of life, and then formulate an answer, because one size does not fit all,” Dow-Hillgartner said.

While taking supplements or herbal medicines seem like a benign health choice, there can be adverse reactions with certain treatments, such as interfering with effectiveness, decreasing the body’s ability to naturally clear a drug out of its system, or exacerbating side effects.

“There are several pretty common supplements that come to mind, like fish oil can increase bleed risk,” Schenkat said. “So we’re also looking at the additive toxicities and do we think this is safe, given the anticipated side effects of your treatments.”

They also cautioned that many supplements on the market do not fully label every ingredient included in them, so that’s another factor to consider. Besides talking to a health care provider, patients can find trustworthy information through Memorial Sloan Kettering Cancer Center’s integrative medicine website, U.S. Pharmacopeia and the Natural Medicines Database.

“These (supplemental and herbal companies) are trying to sell you a product, and they can have claims that quite frankly have not been studied,” Dow-Hillgartner said. “I just encourage all patients to bring all of their supplementals and herbals to us and we can really help to flush out what’s fact versus what’s fiction and what they’re just trying to sell you.”

While they stress caution about supplements and herbals, that doesn’t mean Dow-Hillgartner and Schenkat are completely against them. Both agreed that some ingredients have been studied and proven to show benefit, but it’s still best to discuss with a medical provider if those findings apply to a patient’s specific situation. Among the common supplements they talk about with patients are ginseng, melatonin, vitamin D, calcium and ginger.

Both Schenkat and Dow-Hillgartner said patients should treat supplement and herbal use as an ongoing conversation with their health care providers. While patients may be advised to stop use of them during one treatment, it could be safe at another time or with a different treatment.

“I think it goes back to, is it the right time and right place for this? Is this a supplement that we just need you to pause on because there’s a drug interaction with chemotherapy and it’s something that, six months to a year down the road, it may be safe for you to restart? That’s all part of this discussion,” Schenkat said. “So I think keeping the big picture in mind is important and allowing patients to do the things that are important for them.”