Rush Derangement Syndrome is an idiomatic phrase used by some conservatives to refer to wildly exaggerated overreaction to Rush Limbaugh. Apparently Rush's use of free speech enrages a few liberals. Michelle Malkin identified this ailment back in May 2007. A spokesman from the Baltimore Department of Public Works saw a large billboard with Rush's picture defaced by paint. When someone reported the vandalism, the spokesman said, “It looks like they took globs of paint and threw it on his face. It looks great. It did my heart good.”  Ken Shepherd at Newsbusters.org calls this malady the "Limbaugh Derangement Syndrome." 
Liberals vs Rush Limbaugh
Ever since Rush Limbaugh resurrected conservative talk radio, the liberals have tried to counteract and marginalize him. In 2004, Senator Tom Harkin added an amendment to the 2005 Defense Authorization bill asking that the Secretary of Defense ensure policies of "equal opportunity balance with respect to political programming." 
President Barack Obama vs Rush Limbaugh
In January 2009, just six days after being inaugurated as the 44th President of the United States, President Obama told top GOP leaders, "You can't just listen to Rush Limbaugh and get things done," and he "warned Republicans on Capitol Hill today that they need to quit listening to radio king Rush Limbaugh if they want to get along with Democrats and the new administration."  In February 2009, Malkin said President Obama is afflicted with Rush Derangement Syndrome. "With his explicit attack on Limbaugh during a Capitol Hill meeting last week, Obama has signaled the end of Bush Derangement Syndrome - the defining mental illness of the Democrats for eight years - and ushered in the age of Rush Derangement Syndrome."  Malkin says President Obama is making a big mistake in attacking Rush Limbaugh. "Too bad Obama hasn't learned the lessons of his predecessors. Limbaugh not only has survived countless protests, boycotts, media smears and political attempts to kick him off the airwaves. He has emerged each time with a higher profile, greater influence, and a strengthened hand." 
Democratic Congressional Campaign Committee vs Rush Limbaugh
In January 2009 the Democratic Congressional Campaign Committee "launched an online petition for readers to express their outrage at conservative talk show host Rush Limbaugh for saying last week that he wanted President Barack Obama to fail." 
Senate Democrats vs Rush Limbaugh
The Harry Reid Letter
On October 2, 2007, Senator Harry Reid, D-NV, wrote a letter to Mark P. Mays, President and CEO of Clear Channel Communications, who is Rush Limbaugh's chief patron. In it Senator Reid essentially demanded that Mr. Mays order Mr. Limbaugh to apologize for remarks he made concerning "phony soldiers." A phony soldier is someone who is not a soldier at all but is pretending to be one, especially in a public forum. Such activity is unlawful, and the person whose activity prompted Mr. Limbaugh's remarks has since been convicted and punished.
Mr. Limbaugh obtained that letter, apparently from Mr. Mays' office, and publicly exhibited it to an audience in Philadelphia, Pennsylvania, on October 11. The next day he placed the letter for sale at public auction at eBay.com. Mrs. Betty Casey, trustee of the Eugene B. Casey Foundation and a notable philanthropist in her own right, won the auction and paid more than two million US dollars for the item. Mr. Limbaugh donated the entire proceeds to the Marine Corps-Law Enforcement Foundation and included a matching contribution of his own.
Images of the text of the letter, and the signatures of the Senators, appear below:
Al Franken vs Rush Limbaugh
Back in 1999, Al Franken wrote this book for liberals, "Rush Limbaugh Is a Big Fat Idiot." In 2004, Al Franken takes part in the launch of Air America Radio to counteract the conservatives on talk radio.
The Squad vs Rush Limbaugh
Anti-Semitic Squad members Rashida Tlaib and Ilhan Omar appear to suffer from both Rush Derangement Syndrome and Trump Derangement Syndrome, as the two Democrat Congresswomen left President Trump's 2020 State of the Union address while Limbaugh was being awarded the Presidential Medal of Freedom.
Republicans vs Rush Limbaugh
Occasionally Republicans have attacked Rush as well.
Arnold Schwarzenegger vs Rush Limbaugh
After Rush Limbaugh said Arnold Schwarzenegger was a closet liberal who supported abortion, gay adoption and gun control, Schwarzenegger called Rush Limbaugh “irrelevant” and said, “I am not his servant.” 
Colin Powell vs Rush Limbaugh
- Rush Derangement Syndrome, Michelle Malkin, Michelle Malkin.com, May 10, 2007
- Limbaugh Derangement Syndrome at HuffPo: Radio Host Genocidal to Dems, Ken Shepherd, Newsbusters.org, May 7, 2008
- Liberals vs. Limbaugh: The Harkin Fumble, Center for Individual Freedom
- PREZ ZINGS GOP FOE IN A $TIMULATING TALK, Charles Hurt, New York Post, January 26, 2009
- Rush Derangement Syndrome, Michelle Malkin, Michelle Malkin.com, February 1, 2009
- THE RUSH REVIVAL, Michelle Malkin, New York Post, January 31, 2009
- Democrats Launch Petition Against Rush Limbaugh, Melanie Hunter-Omar, CNSNews.com, January 27, 2009
- Reid, Harry, et al. "Letter to Mark P. Mays of Clear Channel Communications." Electronic Office of US Senator Harry Reid, October 2, 2007. Retrieved October 19, 2007.
- Limbaugh, Rush. "The Anatomy of a Smear: 'Phony Soldiers' Is a Phony Story." Rush Limbaugh Official Site, accessed December 25, 2007.
- Auction listing of original of Harry Reid letter. eBay.com. Retrieved October 19, 2007.
- Al Franken vs. Rush Limbaugh, David Skinner, The Weekly Standard, March 26, 2004
- , NBC’s Today show
- Colin Powell on Rush Limbaugh, YouTube, December 16, 2008