Dear Scriptor,

I goofed and closed the question (Question ID #177269), but your
excellent (VERY timely and on point) research deserves to be paid for.
 
Please post an answer to this & (if possible) explain how to get you paid
and rate your answer.

Many thanks,

David

Dear davidhardwick,

Since your original question already expired, I'm simply posting the
full answer here:

On 18 July 1955, Kremers Urban Co. filled the application for
registration of "Levsin" as trademark for their hyoscyamine sulfate
drugs at the United States Patent and Trademark Office.
According to the Office's records, Kremers-Urban made first use in
commerce of the drug behind the name "Levsin" already earlier that
year, on 09 June 1955. I assume that the FDA approved the drug not a
long time before that first use in commerce, in the weeks or months
before 09 June 1955.
The final registration of the term "Levsin" as a trademark dates from
27 March 1956. I think that, though the drug itself has seen
commercial use half a year before that date, Kremers Urban did not use
a trademark not yet fully protected. So "Levsin" as a trademark drug
was introduced that year, while the generic drug itself saw first
commercial use already half a year earlier.
Kremers Urban became, by acquisition, part of the German company
Schwarz Pharma in 1986.

Sources:

United States Patent and Trademark Office: Online Database
http://www.uspto.gov/

Schwarz Pharma USA: Company History
http://www.schwarzusa.com/ab/sp_usa_history.htm

Please don't worry about how to pay me; I will get my share of the fee
you offered automatically.

To rate my answer, log in to your Google Answers account. On the "My
Questions" page, you'll see a list of all the questions you've asked
so far. Click on the question whose answer you want to rate. Please
note that one single star stands for a very poor answer, while five
stars indicate a fully satisfying answer. Rate the answer and add a
comment in the dialog box to explain your rating. Then click the
"Submit Rating" button to post your rating to the site.

In case you are extraordinary satisfied with the answer you received,
you also get an opportunity to leave a tip. Just enter an amount in
the tip box next to the rating. The researcher will receive 100% of
the amount you tip them; Google will not take a percentage of the tip.
Please note that you are not at all obliged to tip; it's only for very
good service.

Search terms used:
levsin approval fda
://www.google.de/search?q=levsin+approval+fda&ie=UTF-8&oe=UTF-8&hl=de&meta=
"SCHWARZ PHARMA" "kremers urban"
://www.google.de/search?hl=de&ie=UTF-8&oe=UTF-8&newwindow=1&q=%22SCHWARZ+PHARMA%22+%22kremers+urban%22&btnG=Google-Suche&meta=

Hope this is what you were looking for!
Best regards,
Scriptor

After hours of searching myself, I submitted my original question to
Google Answers.  Scriptor's answer was fast, accurate, and absolutely
on point.

Scriptor rocks!