He was taken to Care Hospital in Hyderabad.
"Rajendra Prasad suffered a mild stroke when he was brought in. However, in less than 20 minutes his condition was brought back to normal," Somaraj, a doctor at Care Hospital, told IANS on the phone from Hyderabad.
"He's perfectly fine now and will be discharged by evening, tentatively around 7.30 pm," he added.
The 56-yr-old actor was administered angioplasty.
Director Sagar Chandra, who worked with the actor recently in the Telugu film "Ayyare", told IANS: "I spoke to Rajendra Prasad's secretary Naga Raju in the evening and he said the actor is much better now. There is no reason to worry."
In a career spanning three decades, the actor has starred in more than 200 Telugu films, besides being part of few Tamil films. He earned the title of 'King of Comedy' after starring in some of the best comedies.
He also won the prestigious Nandi awards twice for "Erra Mandaram" (1991) and "Aa Naluguru" (2004).
He was allowed to walk the green carpet at the International Indian Film Academy (IIFA) film festival in 2009, marking his performance in the Bollywood film, 'Quick Gun Murugun'.
'Rock On 2' trailer launch: Farhan, Shraddha enthrall audience with live gig
Flashback: When bikini babes set a new world record in Australia
Photos: Ajay Devgn launches 'Shivaay' comics at Mumbai Comic Con
Photos: 'Rock On 2' stars Farhan, Shraddha on 'Yaaron Ki Baraat'
Photos: WWE star Sheamus and John Abraham clash in Mumbai