Former All Black Sione Lauaki will see a specialist in London after tests indicated he is suffering from renal failure and cardiovascular problems.
Lauaki now plays his rugby in France for Bayonne but has been told not to play or train for the rest of this season because of concerns for his health.
"I have seen specialists in Bayonne and Bordeaux, and after having consulted with each other and the Bayonne team doctor, we agreed it was important to get another medical opinion," Lauaki, 30, told French newspaper L'Equipe.
"What has happened to me is disappointing. I've never had these types of problems before but that's life – and it's necessary for me to look after myself."
Lauaki saw a nephrologist (kidney specialist) and a cardiologist (heart expert) in Bayonne and visited French Rugby League's cardiologist based in Bordeaux before ending his career to start medical treatment.
Laukai has been sent messages of support through his Twitter account and responded by saying, "Thanks to everyone for the tweets and support, I'm good so no need to panic, life is good even the part that's not."