HD Kumaraswamy had undergone heart-related surgery in the past.
JD(S) leader H D Kumarswamy, who has been hospitalised with symptoms of exhaustion and general weakness, is "medically stable and is recuperating", the hospital treating him said on Sunday.
The former Karnataka Chief Minister's office said the 63-year old leader, who had been touring tirelessly, was suffering from fever and was advised by doctors to rest.
"Mr H D Kumaraswamy was admitted on April 22, 2023 evening to Manipal Hospital, Old Airport Road Bengaluru under care of Dr Satyanarayana Mysore. He is admitted with symptoms of exhaustion and generalised weakness," the hospital said in a statement "All relevant medical tests and treatment are being carried out. He is medically stable and is recuperating," it said.
Mr Kumaraswamy has been travelling extensively, campaigning for JD(S) candidates across the state, ahead of May 10 Assembly polls in Karnataka.
Mr Kumaraswamy has requested JD(S) workers and leaders not to worry, and that he will participate in the election campaign after resting, his office said in a statement.
Mr Kumaraswamy had undergone heart-related surgery in the past.