Kelpie Dung is used as a medicine for animals that takes the sting out of the most terrible bites.
When Grady first used this, Sophie plugged her nose in reaction to its terrible scent, which she compared to death, rot, and tuna fish.
It appears as a brown slime, which is easily spread. From what is seen of it, it is stored in a jar.
Official Description[]
The waste from a kelpie can take the sting out of terrible bites applied to the skin.