A drawing ointment is very old-fashioned goo, which is typically tawny or black in color. In fact, it is often called a black ointment, drawing salve, or unguent. The use of this old remedy goes back deep into time and was a trusted method of dealing with slashes, gashes, boils and bumps. Likely, the ingredients changed with time and with what was available.
I recently had an old standby drawing salve used on me. Smack dab in the middle of my back, just exactly where you can't reach, a small sebaceous cyst started getting larger. These cysts are made up of skin/hair oil that becomes sort of like cottage cheese under the skin but is a distinct lump. The way to the surface from the oil gland gets clogged so the sebum (oil) gets backed up and hardens.
The medical way to deal with these is to wait and watch until they become too annoying or too large. Then they are cut out with minor surgery and typically sent for lab testing. I decided to try a product called Smile's PRID instead. If I had been told in advance of how well it worked, being skeptical, I might not have believed it.
I applied the drawing salve twice each day, once at bedtime and then again in the morning after showering. For the first couple of days the bump just turned red but shortly started itching. Because it was located where I couldn't get to it, I had to have a little help. The helper must be able to tolerate some icky stuff, so find someone who likes to pop pimples.
With a little bit of pressure from washed hands the PRID caused an eruption of old oil (not pus). Afterwards, a clean bandage would be placed over the newly salve-coated cyst.
This was repeated for about 10 days until the itching went away and expressing the cyst didn't produce any oil. The bump almost disappeared completely from the size of a quarter to the size of a BB. It may not have gone away for good, but for now... impressive!