I actually thought the link above was pretty credible if read carefully. The author stated that most of the agents in pills are known to be pretty harmless, even if folks might actually be allergic to them. As stated in the article, many pills are 2/3 to 3/4 inert ingredients - just to make the pills larger and easier to handle, manage, swallow, or to help with absorbtion in the GI tract. There are certainly items that the occasional individual might not tolerate, especially if they are taking, not one pill, but maybe 6-12 or even more daily. Mostly these might be folks with an extreme sensitivity to gluten or to some foreign protein they are allergic to. But remember, even foreign protein is routinely digested in our stomach, just like the meat in our sandwich.
Ineret ingredients in oral meds are a different situation than inert ingredients in injectable medication of course. Injectables have a much more restrictive list of acceptable ingredients and distinctions are made whether the agent is to be injected intra-muscular, subcutaneous, or intravenously. There is no overlap for the proper use of injectable agents. @Chris pointed out that the aluminum in an injectable vaccine is so low as to be insignificant compared to what we all eat every day. One needs to read carefully the amounts of things present in drugs - modern chemistry with spectrometry can find almost anything in our usual daily food - arsenic, lead, uranium, etc that sound terrible - but it is the amounts that really matter, not just the presence of minute biologically insignificant traces. Theoretically non of us should have lead in our serum, but we all have measureable levels, even if they don't seem to be toxic levels.
Someone mentioned something about injecting metals intravenously with vaccinations. I would like to point out that most vaccinations, like flu, are intra-muscular injections ie: into muscle bundles, not intravascular in any form or manner.
Some vaccinations are subcutaneous or intra dermal - small pox was performed by scarifying the epidermis. I was vaccinated for smallpox as a child and again in early 2002 after the weapons grade anthrax attacks following 2001, so that I could be safe examining folks for ophthalmic small pox if it were ever used, It was not,
Some vaccinations are oral - Polio vaccine is oral these days also.
A good source for some information about inert ingredients in tablets, pills, etc
One further thought, I found many folks who stated that they were allergic to a drug in their medical history they provided me, but when I pointed out that the symptoms they described as allergic was actually a known side effect/symptom reported by a known specific percentage of patients taking that drug, the patients admitted that they just didn't want to take that drug. They didn't like it. Hopefully, their life will never truly need that drug that they warned their caregivers they were allergic to. The first link above briefly discussed just this issue, that errors/lies told by patients, in medical records can adversely harm patients, inadvertently.
With a paper record in my office years ago, I could correct these errors. With modern secure electronic medical records it is very difficult, if even possible, to correct these kinds of medical record errors.......
I don't think inert ingredients in medications are a very significant issue. They are worth thinking about if the patients is not responding as expected. But one of the things good doctors are routinely taught, is, if a patient is not responding as expected to a new drug, at least consider stopping it and starting over with a new medication after a withdrawal period. Very basic medical training, really.