Jailed former Georgian president Mikheil Saakashvili, who has been on a hunger strike, was given a blood transfusion late on Friday and is in stable condition.
Interfax news agency quoted his personal doctor as saying on Saturday.
The pro-Western politician, who declared a hunger strike on October 1, was arrested after returning to Georgia, having lived abroad for years.
He faces up to six years in jail after being convicted in absentia in 2018 of abuse of power and concealing evidence when he was president, charges he rejects as politically motivated.
"One of the parameters of Saakashvili's blood test was bad, so local prison doctors and an emergency ambulance team helped me with the transfusion and after that Saakashvili's condition stabilised," Nikoloz Kipshidze, Saakashvili's doctor, was quoted as saying by Interfax.
Kipshidze believes that Saakashvili should be transferred to a city hospital because "the crisis can recur and it would be difficult to cope with it in a prison hospital," Interfax added.
The 53-year-old Saakashvili led the Rose Revolution in 2003 that ousted veteran leader Eduard Shevardnadze. Saakashvili ruled as president from 2004 to 2013 before leaving the country and building a new political career in Ukraine.
He was arrested and jailed on October 1 after returning home on the eve of parliamentary elections to rally the opposition and "take part in saving Georgia".
Last week thousands of his supporters rallied in the capital Tbilisi to demand his release.


US strikes Iran in response to attack on cargo ship in Strait of Hormuz
Bahrain condemns Iranian drone attacks on its territory
Venezuela quake toll tops 900, search intensifies for hundreds trapped
Germany hit by record temperatures as heatwave moves east
Israel, Lebanon sign framework peace deal after US-mediated talks
