“Laughter is a tranquilizer with no side effects” is a saying that has been printed on many images.
   
“Laughter is a tranquilizer with no bad side effects” was printed in the Titonka (IA) Topic on February 7, 1974. “Laughter is a tranquilizer with no side effects” was printed in The Spokesman-Review (Spokane, WA) on February 21, 1974.” Laughter is a tranquilizer with no side effects. Glasow” was printed in the Langley (BC) Advance on February 28, 1979. The saying is from American humorist Arnold H. Glasow (1905-1998).
 
         
Answers.com
Q: Who is Arnold Glasgow?
A: He was my father-in-law. Arnold Henry Glasow (notice no second g in last name) was born in Fond-du-lac, Wisconsin in 1905, and died in Freeport, IL in 1998 at age 93. He graduated from Ripon College, and started his own business when he moved to Freeport just after the depression. His business was a humor magazine that he marketed to firms nationally, which firms would turn it into their “house organ” to send to their customers. He carried on this business for over 60 years, publishing his first book at age 92. The book is titled, “Glasow’s Gloombusters,” one of the many titles he put on his work during his career. He was cited frequently in the Wall Street Journal, Forbes, the Chicago Tribune and many other major organs. He was a regular contributor to the humor sections of Reader’s Digest. Sixty years of productive work. Many attributions. A real American thinker, self-effacing and generous of spirit, he shunned the national spotlight.
   
Newspapers.com
7 February 1974, Titonka (IA) Topic, pg. 3, col. 6:
Laughter is a tranquilizer with no bad side effects.
 
Newspapers.com
21 February 1974, The Spokesman-Review (Spokane, WA), “Shop with Sue,” pg.3, col. 6 ad:
Laughter is a tranquilizer with no side effects.
 
Google Books
The American Bicentennial Almanac & Reader
By Robert L. Smock
Virginia Beach, VA: Donning
1975
Pg. 150:
And we’re crying, because we can’t remember who said “Laughter is a tranquilizer with no side effects.”—Ed.
 
Newspapers.com
28 February 1979, Langley (BC) Advance, pg. 3A, col. 2:
Laughter is a tranquilizer with no side effects.
Glasow
 
Google Books
The Reader’s Digest
Volume 130, Issues 777-782
1987
Pg. 17:
Laughter is a tranquilizer with no side effects.—Arnold H . Glasow
   
Google Books
Aerobics for the Spirit
By Robert Morley
Dallas, TX: Word Pub.
1990
Pg. 184:
Laughter is a tranquilizer with no side effects .—Arnold Glason
 
Google Books
Humor, Play, & Laughter:
Stress-proofing Life with Your Kids
By Joseph A. Michelli
Golden, CO: Love and Logic Press
1998
Pg. 34:
American humorist Arnold Glasgow said, “Laughter is a tranquilizer that has no side effects.”
 
Google Books
Humorous Wit
By Djamel Ouis
Paragon Publishing
2020
Pg. 380:
Laughter is a tranquilizer with no side effects.
Arnold H. Glasow