Goldenseal in pregnancy and breastfeeding

What NCCIH says about safety

In small research studies, goldenseal has been administered at doses of about 3 g per day for short periods of time without serious harmful effects. The safety of taking goldenseal for longer periods is uncertain. Some commercial goldenseal products have been found to contain other herbs or ingredients not listed on the label in addition to or instead of goldenseal. Goldenseal may change the way your body processes many medications. For example, a study funded by the National Center for Complementary and Integrative Health (NCCIH) found that levels of metformin—the most commonly prescribed diabetes medicine—decreased about 25 percent in healthy adults who were given goldenseal extract plus metformin. This drop was enough to potentially hinder glucose control in people with type 2 diabetes taking metformin. If you take any type of medicine, talk with your health care provider before using goldenseal or other herbal products; some herbs and medicines interact in harmful ways. Women who are pregnant or breastfeeding should not use goldenseal, and it should not be given to infants. The berberine constituent of goldenseal can be harmful to newborns.

Quoted in full from NCCIH so nothing is lost in summarising. Where they say “little is known”, that means the studies do not exist — not that the herb is known to be safe, and not that it is known to be harmful.

How much is actually known

There is not enough evidence to determine whether goldenseal is useful for any health conditions. More research would be needed before any conclusions can be reached.

What the research has found

No rigorous studies have been done to evaluate the effects of goldenseal on health conditions in people. Berberine, a substance found in goldenseal, has been studied for its effects on blood sugar, blood cholesterol levels, body weight, and other health-related outcomes. However, when people take goldenseal orally (by mouth), very little berberine may be absorbed by the body, so study results on berberine may not apply to goldenseal.

Before you take this

Dose and form change the answer completely. A culinary amount of a spice, a cup of tea, and a concentrated supplement extract are three different things, and most research is done on the last of them.

Supplements are also not regulated like medicines, so strength and purity vary between products. Bring the actual bottle to your midwife, doctor or pharmacist — that conversation is worth more than any page, including this one.