Pharmakon

In schools, they teach that the greek word φάρμκον means both "drug" and "poison", since any drug has collateral effects and can be a poison if used in an inappropriate way. I was cotnent with this, whena I have read in Pliny’s Historia Naturalis, in the book about plants, a passage where he states more or less the following “up to now we have considered remedies that everybody can use, but now we must consider the φάρμκα that can be administerd only by physicians” and among these drugs were aconite, henbane, and other very dangerous poisons. In other words, φάρμκον has no ambiguous meanning: it means strictly “poison” since physicians used poisons to “kill” the illness – something not very different perhaps from chemotherapy, where deadly poisons are administered to cancer patient in the hope that the cancer will die before than the rest of the organism.