Fianna Fáil TD John McGuinness was hospitalised last week after contracting viral meningitis.
Last Friday the Kilkenny-based TD was rushed to St Luke's hospital in the city, where he remained over the weekend.
He is now at home recovering from the illness and will be recuperating for a number of weeks.
He could not be contacted yesterday, but his son Andrew, a city councillor, said his father was "doing well".
He is expected to be back in the Dáil in the autumn, although he will not be attending the Fianna Fáil Parliamentary Party meeting in Westport next week.
"It was viral meningitis. It was just something he wasn't expecting," he said. "But he's doing well. He'll be at home for a few weeks."
The viral meningitis strain is distinct from bacterial meningitis, which can be lethal.
Mr McGuinness told the Kilkenny People newspaper earlier this week that the incident had given him "the fright of my life".
"I had headaches and an upset stomach last week. I was very busy in the office and thought it was some kind of bug," he told the newspaper.
"I didn't bother going to the doctor, but on Friday I got a turn for the worse and the pain became very severe. I couldn't tolerate any light and my neck was stiff.
"I have learned a valuable lesson. I should have gone to the doctor at the start of the week instead of the end of the week. If you're sick at all you're better off getting it checked out immediately," he said.
Mr McGuinness attended the medical assessment unit at St Luke's.
"I am still very sore and very weak after all the treatment. I was given antibiotics every four hours through a drip. It has taken a lot out of me and I will be out of action for the next few weeks," he added.