Recently someone commented on my blog, mentioning that she has had severe reactions to injections over the past few years and suspects polysorbate 80 as the cause in at least one of them.
Polysorbate 80 is made from polyethoxylated sorbitan (chemical compounds derived from the dehydration of sugar alcohol) and oleic acid, a fatty acid found in animal and vegetable fats. It is a common ingredient in foods, and cosmetics. I was surprised to find out that it is also commonly added to injections as an emulsifier and to vaccines as a way of increasing the immune system’s reaction to the vaccine. Other names for polysorbate-80 that might be seen on shots include brand names such as Alkest, Canarcel and Tween.
It is widely accepted that injected, polysorbate 80 increases cell permeability, including helping things cross the blood-brain barrier. Immune system reactions are pretty widespread, meaning that it happens in people without allergies to oils, but I would imagine that such reactions would be more violent in people with allergies.
I will say if you have any sensitivities to fats or oils, avoid injections with polysorbate 80 in them if you can. Someone may point out that the amount of polysorbate 80 in shots is tiny. Not high enough to cause issues, but as someone who suffers from allergic reactions I can personally say the amount of a substance is hardly proportional to the amount of damage that that substance can cause when the body reacts poorly to it.
It can be difficult to find out what shots contain. Apparently nurses and doctors often don’t reveal what is in injections for fear of upsetting patients. It might help to ask to read the insert, although I don’t know what the legal requirements are when it comes to labeling drugs or injections.
It seems to me this is just one more unlikely place to look out for oils.