Houndstongue is native to a broad expanse across Europe and parts of Asia. It thrives predominantly in temperate regions, with its native range encompassing the major areas of Northern, Eastern, and parts of Southern Europe, alongside Western and Central Asia. Houndstongue has also been introduced to various other regions, including parts of North America, some countries in Asia, and certain island nations.

Houndstongue is a moderately toxic plant containing pyrrolizidine alkaloids. All parts are harmful and can cause severe effects like nausea, vomiting, diarrhea, and liver damage in both cats and dogs if ingested. Also, the oils can irritate skin, leading to dermatitis. Immediate veterinary care is crucial if ingestion occurs.

Houndstongue is a troublesome weed that grows in most of the contiguous United States, particularly in rangeland. It has seeds covered with barbed prickles that have been referred to as nature's Velcro®, and this helps it to spread easily. Houndstongue appears on state invasive species lists in West Virginia and California and invasive species laws in Wisconsin and western states from Colorado to the Pacific Northwest. It is also considered invasive in several Canadian provinces. Another problem with houndstongue is that it invades crops and pastures and displaces other species. It is toxic to humans and livestock and can cause contact dermatitis. Plants should be dug out, cut, or mowed to the base when flowering.

The ideal time to remove houndstongue is in the spring or early to mid-summer, before the plant produces its characteristic red-purple flowers and spreads its seeds, which could lead to more widespread growth.