“I’m taking Viagra and drinking prune juice—I don’t know if I’m coming or going” is a popular joke. Viagra is trademarked with a first use of April 6, 1998. ” The other day I washed down my Viagra with prune juice and for 5 hours I couldn’t tell if I was coming or going!” was cited on Google Groups: alt.folklore.urban on May 21, 1998. Jeffrey Ross told the joke at a 2001 comedy roast of Playboy founder Hugh Hefner.
 
Popular comedian Rodney Dangerfield (1921-2004) is often credited with the joke, but it’s not clear if he originated it, or when he said it.
     
 
Google Groups: alt.folklore.urban
Thanks to All
JDWall5246
5/21/98
To all of you who responded to my testy comments on AFUista rudeness, the flames and kudos were great. A severe scold however to the guy who said something to the effect that I should “buzz off and drink my prune juice”
 
Listen Kid! Have you ever tasted that stuff? It’s awful. Besides the results can be unpredictable. The other day I washed down my Viagra with prune juice and for 5 hours I couldn’t tell if I was coming or going!
 
6 December 1998, New York (NY) Post, “Call him the court jester: Brooklyn ex-judge now king of zingers as stand-up comic” by Barrett Devlin, pg. 9:
Judge Eugene Schwartzwald, who for years sat on the bench in Brooklyn Criminal Court, spent Friday night on a stage at Pip’s, a legendary comedy club in Sheepshead Bay where many other now-famous comics got their start.
(...)
“I took too much prune juice with my Viagra, and now I don’t know if I’m coming or going.”
   
Google Groups: alt.atheism
Beer
Fred Stone
9/11/01
(...)
Henny Youngman invented a new drink: Viagra and prune juice.
You won’t know whether you’re coming or going.
 
Google Groups: rec.music.makers.guitar.acoustic
Brian L. Rachford
6/4/02
Viagra humor
Rodney Dangerfield:
“My doctor put me on a Viagra and prune juice diet.  Now I don’t know if I’m coming or going!”
 
Google Books
The Friar’s Club Private Joke File:
More Than 2,000 Very Naughty Jokes from the Grand Masters of Comedy
Edited by Barry Dougherty
New York, NY: Black Dog & Leventhal Publishers, Inc.
2006
Pg. 155:
Hugh Hefner has always been a sexual innovator. He was the first person to mix Viagra with prune juice. Now he doesn’t know if he’s coming or going.
—JEFFREY ROSS, HUGH HEFNER ROAST, 2001
 
Twitter
Missy K
‏@BestofAdultToys
“I’m taking Viagra and drinking prune juice - I don’t know if I’m coming or going.”  Rodney Dangerfield
10:50 PM - 7 Apr 09
 
(Trademark)
Word Mark VIAGRA
Goods and Services IC 005. US 006 018 044 046 051 052. G & S: compound for treating erectile dysfunction. FIRST USE: 19980406. FIRST USE IN COMMERCE: 19980406
Mark Drawing Code (1) TYPED DRAWING
Serial Number 75089201
Filing Date April 12, 1996
Current Basis 1A
Original Filing Basis 1B
Published for Opposition November 26, 1996
Registration Number 2162548
Registration Date June 2, 1998
Owner (REGISTRANT) PFIZER INC. CORPORATION DELAWARE 235 East 42nd Street New York NEW YORK 10017
Attorney of Record Heather McDonald
Type of Mark TRADEMARK
Register PRINCIPAL
Affidavit Text SECT 15. SECT 8 (6-YR). SECTION 8(10-YR) 20070718.
Renewal 1ST RENEWAL 20070718
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