I have never heard of Medicare causing shortages due to the MMA of 2003.
you can look up drug shortages on a few sites like:
http://www.ashp.org/Drugshortages/Current/or
http://www.fda.gov/Drugs/DrugSafety/DrugShortages/default.htmMost shortages are caused by lack of supply's and sometimes due to the location (weather, war, foreign country issues Etc.) also it may depend on if the manufacture owns the patent on the particular drug in which they can control the supply and demand.
perfect example is Shire Pharmaceuticals, Adderall XR.
Adderall XR formula is still patent protected until 2018 so they control production and cost of this drug. they have also sued and or purchased any company who tries to make Adderall XR.
example (Watson Pharmaceuticals)
Here is an example from ashp.ord on there drug shortage page -
Hospira has propofol on shortage due to manufacturing delays.
Teva discontinued all propofol presentations in May, 2010.2
APP is releasing generic propofol to wholesalers as product gets released due to increased demand. Diprivan is readily available.
Estimated Resupply Dates
Hospira has propofol 10 mg/mL vials on back order and the company estimates a release date of August, 2012 for the 20 mL and 100 mL vials. The company cannot estimate a release date for the 50 mL vials; however, emergency supply of the 50 mL vials may be available for direct order.
APP has propofol and Diprivan on intermittent back order and the company is releasing product as it becomes available on a regular basis. Check wholesalers for supply.
Sorry for the late response I just found this site.