Until recently, the English language lacked a single, punchy, positively flavoured noun to describe a medicine's (greater or lesser) freedom from side effects. Whereas German has its Verträglichkeit (from sich vertragen—to agree with something or someone), a word that emphasises the positive aspect of something being well tolerated, all that could be found in English was more or less verbose phraseology, such as a good side effect profile, without any irritant effect, etc, invariably dragging in the idea of something adverse—not only clumsy, but, surely, a pharmaceutical copywriter's nightmare. Quite obviously, this was a void that needed filling.
And filled it has been, to a large extent, by the adoption, over the last 10 years or so, of tolerability (a term used, in non-pharmaceutical contexts, since at least 1640). While a copywriter would still be extremely ill advised to describe a firm's new wonder drug as tolerable (remember the Thurber dinner party: “This claret is really quite tolerable considering it cost only $2 a bottle”?), to say that it has tolerability is now okay. In fact, this acceptance goes beyond the realm of advertising: a trawl through the BMJ on the internet (January 1996 to May 1999) produced 10 instances of the use of tolerability in titles or abstracts, and 53 in papers (plus one isolated hit on the less euphonious and no more justifiable tolerableness). The incidence would have been even higher had the use of the term in advertisements, over the same period of time, been factored in. No doubt, some purists will still jib at this usage. However, tolerability, it seems, is here to stay. It may not be ideal, but it will do—tolerably well.
Footnotes
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