Widely distributed across Europe and eastern North America, L. piperatus has been accidentally introduced to Australia.

[3] For many years, Tyrolian naturalist Giovanni Antonio Scopoli was considered the author of the first description, until a 1987 revision of the International Code of Botanical Nomenclature began considering primary works describing fungi from as far back as 1753, instead of only 1821 (based on the work of Swedish naturalist Elias Magnus Fries).

[9] Phylogenetic research showed that L. glaucescens, sometimes considered only a variety of L. piperatus, is a distinct species in Europe.

[10] Furthermore, the existence of at least ten lineages worldwide, with no overlap among continents, was shown for the group around L. piperatus, suggesting that populations in North America might actually be distinct species.

[11] Russula delica is similar in colour and shape, though has adnate blue-green tinged gills and no milk.

[16] L. deceptivus is also similar, but is differentiated by its less crowded gills, firmer cap margin and less acrid milk.

[20] Lactifluus piperatus in the wide sense, i.e. including probably several species,[10] is found in Europe,[11] the Black Sea region in northeastern Turkey,[21] and eastern and central North America east of Minnesota.

[16] The species contains toxins, but despite being described by some mycologists as inedible[25] or even poisonous,[23][26] Lactifluus piperatus is often considered edible.

[20] When eaten fresh and raw, the mushroom has been known to cause an irritant reaction on the lips and tongue, which subsides after an hour.

[20] Lactifluus piperatus forms part of an unusual and highly regarded dish in North America, being one of several species parasitized by the lobster mushroom Hypomyces lactifluorum.

[30] Because of the presence of auxins in Lactifluus piperatus metabolites, it can be applied as a rooting hormone to aid the growth of seedlings of various species of plants, including hazel, beech and oak.