It appears that, due to the increased demand for desiccated thyroid hormones, the supply has not been able to keep up. Both Armour and Nature-throid are reportedly backordered and this could go on for, what some are estimating, 90 days.
Whatever the reason, those of us who are depending on these meds are in a bit of a quandry. I've called the Walgreen's in my area and had them hold what Nature-throid they've got for me (but it's only 30 1 gr tablets). I will also look into ordering the Canadian Thyroid (Erfa Thyroid) online (which you can do without a prescription). But since the main issue is the supplier of all of north America being short of porcine thyroid powder, Canada will likely run short too until the supply can be increased to meet demand.
While I find this very inconvenient and may even be forced to ask for synthetic T3 and T4 until it's resolved, I am also very encouraged that so many are going back to this time-tested and excellent method of treatment, despite all the attempts by Big Pharma to trash it and even remove it as an option. So I guess I can make room for everyone and wait until the supply gets sorted out.