Drugs

On page 13 of his latest book Sounds Interesting (2014, CUP), John Wells writes:

"When my cardiologist started me on a drug called amiodarone, he pronounced it ˌæmiˈɒdərəʊn, and that's what my GP said, too. But shortly afterwards I went for a blood test. The phlebotomist called it ˌæmiˈəʊdərəʊn.

So should it be ɒ or əʊ? A short o or a long one? Who cares? The spelling's the same, which is what matters for the pharmacist who has to dispense it."

Look at this panel: 

How do you say, for example, diltiazem? I'm pretty sure both native speakers and non-native speakers of English will find it difficult to answer this question. As you can see from this link, Wikipedia has dɪlˈtaɪəzɛm (= dɪlˈtaɪəzem), as do Forvo and Merriam-Webster Online. But my Dictionary of Nursing (Adams et al (2007), A & C Black) and my Dictionary of Medical Terms (Bateman et al (2004), A & C Black) say we should pronounce it as dɪlˈtaɪəzəm. In the Oxford Dictionary of Nursing (Martin (2014), OUP), on the other hand, the only pronunciation provided is dil-ti-ă-zem (= ˈdɪltiəzem).

What about betaxolol? Is it GB bɪˈtæksəlɒl, bəˈtæksəlɒl, beˈtæksəlɒl or indeed bɪˈtæksəʊlɒl, bəˈtæksəʊlɒl, beˈtæksəʊlɒl? Who knows exactly?! And are the variants ˌbiːtəksˈəʊlɒl/ˌbeɪtəksˈəʊlɒl even possible in GB?  (Cf. metaprolol/metoprolol which can be both GB ˌmetəˈprəʊlɒl and məˈtæprə(ʊ)lɒl/məˈtəʊprə(ʊ)lɒl/mɪˈtæprə(ʊ)lɒl/mɪˈtəʊprə(ʊ)lɒl.)

John Wells points out in his book that,

"[a]s with so many learned, scientific or technical words, the spelling is fixed while the pronunciation fluctuates. (...) That's because instead of hearing other speakers and imitating what they say, we often create a pronunciation for ourselves on the basis of the spelling, using the reading rules of English, which are notorious for their uncertainty."  

Italian-speaking members of the clinical professions intending to work in the health care sector with English-speaking patients can find information on the pronunciation of medical terms (including medications) in my two books L'inglese medico-scientifico: pronuncia e comprensione all'ascolto (2014, EdiSES) and Health Care Professionals Speaking (2015, EdiSES).