Google:
estradiol valerate shortage
and one of the first results is ashp dot com, which states this:
Estradiol Valerate Injection
[17 June 2015]
Products Affected - Description
Estradiol Valerate Injection, Perrigo
40 mg/mL, 5 mL vial, 1 count (NDC 00574-0872-05)
Delestrogen Injection, Par Sterile Products
40 mg/mL, 5 mL vial, 1 count (NDC 42023-0112-01)
Reason for the Shortage
Par states the reason for the shortage is manufacturing delay.
Perrigo states the reason for the shortage is manufacturing issue.
Available Products
Estradiol Valerate Injection, Perrigo
20 mg/mL, 5 mL vial, 1 count (NDC 00574-0870-05)
Delestrogen Injection, Par Sterile Products
10 mg/mL, 5 mL vial, 1 count (NDC 42023-0110-01)
20 mg/mL, 5 mL vial, 1 count (NDC 42023-0111-01)
Estimated Resupply Dates
Perrigo has estradiol valerate 40 mg/mL 5 mL vials on back order and the company estimates a release date in August 2015.
Par Sterile Products has Delestrogen 40 mg/mL 5 mL vials on back order and the company estimates a release date in January 2016.
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And according to a SF Chronicle article from June, it is implied that despite manufacturers claiming production difficulties, for some reason it is the lower profit generics (vs high profit proprietary drugs) that remain perpetually or cyclically on the shortage lists. I'm guessing drug companies like to keep the factories at capacity with the high profit stuff and although estradiol valerate is important to some people and saline IV bags to others, neither provides as high a return on shareholder investments as some of the newer customized drugs...