Ubi pus, ibi evacua
Ubi pus, ibi evacua is a Latin aphorism or adage, often cited in medicine, that literally means: "where there is pus, there evacuate it". It refers to what clinicians should do when there is a collection of pus in the body, i.e. to create an opening for it to evacuate. Examples include what an otorhinolaryngologist will often do in case of a child with chronic recurring otitis media: he will insert a grommet in the eardrum to help evacuate the excess fluid within. Antibiotics often have difficulties getting into an abscess, and don't work well because of a low pH; evacuation on the other hand will remove a large number of bacteria thus greatly aiding the resolution of the infection.