(AP) The U.S. Food and Drug Administration says some herbal medicines may cause severe side effects and could be dangerous to use.
The agency released a draft guidance Thursday that clarifies the guidelines for herbal medicines, including how to use them.
The guidance is for use of herbal medicines such as tea and ointments, cough drops, and creams, and includes information about safety and side effects, according to the FDA.
The FDA says there is no safe dose for the herbal medicines sold in the U.K., and it recommends using the lowest effective dose possible.
It says some of the drugs are available in generic form.
The agency says the herbal products contain ingredients from plants including tea tree, mint, rosemary, and sage.
They contain other herbal ingredients including herbs that contain caffeine and vitamin C.
The draft guidance says that while some herbs contain more than one active ingredient, there is a clear scientific distinction between what one herbal ingredient does and what other ingredients do.
It says the active ingredients of a product must be used in the correct amounts and for the correct dosage in order to provide a safe and effective benefit.
It also says that herbal products that are sold in combination with a prescription drug, such as prednisone, do not need to be used together.
The drug company that makes the herb must also provide a list of approved uses for the product, the FDA says.
The FDA says it has not made a determination on the validity of the products used in these combinations.
The information about adverse effects comes at a time of heightened concern over the use of some prescription medicines and over the increasing use of alternative treatments, especially herbal medicines.
In recent years, the number of prescriptions for anti-depressants has skyrocketed, leading to concerns about side effects.
The herbal medicines are sold at a discount to mainstream drugs, but they have been blamed for helping many people regain weight and improve their quality of life.