[De epidemia et peste]

sanguine adolescents once in each month before eating, either from the median vein or the hepatic, sometimes from the splenic; for through such phlebotomy, the boiling of the blood or choler in the veins ceases, or such boiling is prevented. And it ought to be done in small quantity, since if they were to fall into a fever or a pestilential disease, it would be bled according to what is to be said below and according to the doctrine of the ancients. This particular phlebotomy ought to be done unless some particular [factor] prevents it, such as weakness of strength, smallness of the liver, pregnancy, or the flux of hemorrhoids or menses. Whence Rasis: "If, however, any movement of blood appears in the body, one must insist upon phlebotomy without delay." And it seems to me that it is worth much before they fall into sickness, because Avicenna says: "And you ought to know that while these illnesses are feared and they have not yet set in, bloodletting is granted to them more securely." Avicenna, Fen IV of the first [book], chapter 30.

Chapter Five: On preservation from an epidemic with foods and drinks.

Since a bad regimen harms the preservation of health, therefore the third aid is taken from foods and drinks appropriate to this disposition. Foods, therefore, that are suitable for them should be foods of light digestion, not easily corruptible, and resistant to putrefaction, and not in as great a quantity as at another time, because one must fear indigestion and, consequently, corruption. But let them be taken more quickly and frequently, so that one never suffers hunger nor thirst. Beware of pork and beef and of great walking animals, as Haly says.