In TCM, it's common practice to use some toxic herbs to relieve a condition (think - fight poison with poison). This practice stopped when western governments try to regulate the ingredients in OTC health products, especially when labeling is enforced. But they don't understand the concept of the formula.
The herbalist will counteract the effects of these herbs with something else in the formula. The presence of the toxic herb is required for the combined herbs-alchemical effect in the body. You should trust your herbalist and not scrutinize his intentions. Why do you defeat your initial faith in the product or herbalist?
I learned this concept from 2 skilled and elderly Chinese Medicine doctors who practised for 30 and 50 years. They are retired now.