Oprah Winfrey has moved to strip Dr. Oz of at least a part of his Harpo Productions platform in the wake of mounting claims lodged against him by a group of fellow highly-respected physicians alleging that some of his medical practices and advice border on "quack" therapy.

According to the New York Daily News, the last Harpo radio airing for the Westwood One syndicated "The Daily Dose With Dr. Oz" will be May 29. Up until now, the show has aired on roughly 150 stations and in six of the top 10 radio markets.

As a potential replacement, Westwood sent a letter to affiliates this week recommending the "A Better Life With Dr. Sanjay Gupta," which stars the longtime CNN chief medical correspondent.

Westwood executives gave no reason for the change, but it's no secret Dr. Oz has come under a barrage of criticism in recent weeks stemming from his promotion of several alternative medical treatments and his past endorsement of other controversial medical creations.

After a group of at least 10 doctors sent a letter to deans at Columbia University, where Oz is a long-time staffer, demanding that he be removed earlier this month, the doctor fired back, using his high-profiled platform to charge many of his accusers had their own agendas and to assert that none of his decisions have been motivated by "personal gain."

The Dr. Oz show has aired on Westwood since 2010 and was renewed for another season on Harpo as recently as last September. At the time, Westwood One Executive Vice President Bart Tessler labeled Dr. Oz "a brand and a voice that people trust for great insight."

He later added, "We love being able to connect our listeners to content that can improve their lives."