Queens Park Rangers say they are "closely monitoring" striker Lyndon Dykes after he was admitted to hospital this week.
The Championship club have not disclosed any further details about the Scotland international.
The 27-year-old, who joined the R's from Livingston in 2020, has scored six goals in 29 club appearances this term.
"Stay strong Lyndon. We wish our number nine a quick and safe recovery," Rangers said.
Dykes was substituted in the second half of QPR's 1-1 draw against Swansea on 21 January and missed Saturday's 3-0 defeat at Hull.