Introduction - Uppsala Monitoring Centre

Poison
the cow-pox, that the disposition to sudden cuticular inflammation is
the same on the application of variolous matter’.
2010 Anaphylaxis is an acute, severe, life-threatening allergic reaction in
pre-sensitised individuals, leading to a systemic response caused by
the release of immune and inflammatory mediators from basophils
and mast cells. At least two organ systems are involved, such as the
skin, the upper and lower airways, and the cardiovascular,
neurological, and GI systems, in this order of priority or in
combination. Allergy to medicines, food, immunotherapy, or insect
stings is the most frequent cause. Similar symptoms caused by nonimmunological
mechanisms are termed anaphylactoid reactions.
(bestpractice.bmj.com/bestpractice/monograph/501/.../guidelines.html).
The change in the
definition over time may explain the different uses of the word.
The use of this term may not be helpful, since as Paracelsus has said, it is a
question of dose. There are five different circumstances:
Where there is a single active principle in a specific species of a herb and it is responsible
both for its efficacy and its adverse effect (i.e. a true side effect) and
where the amount of the active principle is reasonably constant so that an accurate
dose can be given, then the word ‘poison’ would be inappropriate.
Again where the single active principle in a specific species of a herb is responsible
both for its efficacy and its adverse effect, but where an accurate dose cannot be
assured, then the term may be appropriate, e.g. if a single farmer always grows the
same species of herb and farms in a constant manner, e.g. harvesting and storing
the herb in an identical manner over time, then the active principle is likely to have a
narrow range and an accurate dose would be possible. However a wholesaler collecting
herbs of different species of the same herb from many countries would be
likely to have very wide limits for the active principle and be unable to guarantee an
accurate dose. A consumer may consider the first sample of the herb to be nonpoisonous
and the second poisonous.
The third possibility is that there is more than one active principle in a herb and
that the active principle responsible for its efficacy is not the same one that is responsible
for its adverse effect. Under these circumstances the ratio between the
two active principles may vary from species to species and crop to crop so that although
an accurate dose may be found for the active principle responsible for efficacy
the dose for the second active principle may be very variable and under these
circumstances the herb may be considered as a poison.