First off: Amazon is NOT my first choice for a source of pharmaceutical. Period.
Second, spin through the comments. Quoted below is an example of exactly what I'm talking about:
>Active ingredient is dextromethorphan. This blocks cough receptors in the brain. Got a cough? Get this!
>2. No extra ingredients. It’s so hard to find pure medicines just for cough. Store shelves are littered with bundled products for all sorts of symptoms. I don’t like taking a bunch of unnecessary meds, so I buy single symptom products like this.
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>Finally, these gels are only sold in some stores. Shelf space is limited, so they rather carry heavily advertised, bundled meds that pay bigger margins. But they are here at Amazon for a great price!
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Point there being, you've got a system where being able to acquire unadulterated formulations of a substance is the exception rather than the norm.
If you look through drug applications or filings with FDA, you will find that many pharmaceutical companies favor highlighting "abuse-resistant" formulations of combo drugs, while downplaying potential harms and that marketshare of the pure drug decreases after an approval of a combo drug is achieved.
I have started to pay more attention to this sort of thing since they started toying with doing the same thing on stuff I take. I can see a blatant flex of incentive shaping when I see it, and frankly, I disagree with it.
Very vocally.