I have been thinking a lot about how easily medical misunderstandings
happen and how easily misinformation can be propagated. Specifically, I have
heard concerns from some patients that the commonly-used laxative, Miralax,
contains antifreeze. Fortunately this is not the case. I helped take care of a
child who had ingested antifreeze during my time in the Pediatric Intensive
Care Unit as a resident at UVa. That is not something we would want any child
to go through.
The confusion comes from the similar-sounding ingredients.
The main ingredient in Miralax is polyethylene glycol and many brands of
antifreeze contain ethylene glycol. It sure sounds like they are almost the
same thing and would probably have the same effects, right? But they aren’t and
they don’t.Consider this. Regular table salt is sodium chloride. It tastes good and we need a certain amount of it to maintain proper electrolyte levels in our bodies. Using too much can increase blood pressure but we all use it and it is not acutely dangerous. One may then think that plain old sodium would react similarly, but it doesn’t. When placed in water, pure sodium reacts violently, bursting into flames. Obviously that would cause a very concerning reaction if it was on your French fries.
So even though the names are similar and both contain sodium, sodium chloride and sodium metal are completely different chemicals with completely different properties and effects. The same is true of polyethylene glycol and ethylene glycol.
So just because two things sound similar and it sounds true
that they are the same, that is often not the case. Come to think of it, that
applies to a lot more in life than just medicine and chemistry.
