Tussionex is the big new cough syrup on the market. Try to think? Was it incredibly expensive? Do you remember the word "polystrirex" on the packaging/script info/prescription label anywhere? Was it potent enough to last through an entire night's sleep, directed for use up to 3 times a day and no more?
Only one cough syrup on the market fits this description, that it Tussionex, as mentioned above. Unlike regular cough syrups that dose every 4-6 hours, Tussionex contains both immediate and sustained release (that's the "polystirex." Plain dextromethorphan is also available in this format OTC in the US).
If the dosage instructions were less stingy and/or the syrup only stopped the cough for a few hours at a time, it could have been any of the hydrocodone based cough syrups above. AFAIK, immediate-release hydrocodone cough syrup has been on the market a very long time and perfectly suitable generic formulations are available.
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