Liverpool manager Jurgen Klopp feels "really good" despite having been admitted to hospital earlier this week, he said on Friday.
Klopp underwent checks before being discharged on Wednesday and returned to work on Thursday. He is set to be in the dug-out when Liverpool host Southampton on Saturday.
It was the German's second visit to a British hospital following an operation to have his appendix removed in February last year.
"I feel really good," Klopp told a press conference at Liverpool's Melwood training ground.
"I am 50 now. Maybe I need to get used to it, but I've been twice already in a British hospital.
"The NHS (National Health Service) is not as bad as you think. I am not ill, which is kind of good news."
Klopp said he had not enjoyed the fuss his celebrity caused in the hospital.
"It was not a marketing thing," he said. "I had people shouting, 'Klopp is in hospital, did you see him?'"
Liverpool are fifth in the Premier League, 12 points below leaders Manchester City, ahead of Southampton's visit to Anfield.
Southampton's Dutch centre-back Virgil van Dijk will make his first appearance against Liverpool since the Merseyside club's unsuccessful attempt to sign him during the close season.
Liverpool had to withdraw their interest after Southampton threatened to report them to the Premier League for making an illegal approach.
But the clubs have since made attempts to repair their relationship and Saints manager Mauricio Pellegrino has given Liverpool encouragement by saying he cannot guarantee Van Dijk will not leave in January.
- 'Be the bad guy' -
Asked if Van Dijk should expect a difficult afternoon, Klopp replied: "You really expect an answer? What happened in the summer? There is absolutely nothing to say on that.
"It should be difficult for every player to come to Liverpool. Hopefully it is a difficult time (for Van Dijk)."
Liverpool have signed Adam Lallana, Dejan Lovren, Sadio Mane, Nathaniel Clyne and Rickie Lambert from Southampton since the Saints returned to the Premier League in 2012 and Klopp said there was a "special relationship" between the clubs.
Lallana is nearing a comeback from a thigh injury, but Klopp said he would be careful to ease the England international back into action.
"There is no rush even when everyone who knows Adam can imagine how ready he is to be part of the squad again," said Klopp.
"He is a fantastic player, but we want to have him for the season. The next few weeks we have games every three days and we will need him for that.
"This is the moment the player wants to be back immediately and I have to be the bad guy and say, 'Not today, maybe tomorrow.'
"Obviously that is not too nice, but I'm doing it for him and for the club. We will use him for sure, but bringing him for 90 minutes is not a good idea and will not happen."
Liverpool skipper Jordan Henderson has overcome a thigh problem that kept him out of action for England during the international break.
Forward Mane will undergo a late fitness test after reporting a slight hamstring problem following his return from international duty with Senegal.