Early Quenya
leuke
adjective. sick, ill; pallid, wan
qámea
adjective. sick
There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.
Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.
A word appearing as qāmea “sick” in Qenya Lexicon of the 1910s, an adjective form of ᴱQ. qáme “sickness, nausea” (QL/76).
Neo-Quenya: Since ᴹQ. qáme “sickness” appears in Tolkien’s later writings (Ety/KWAM), I would retain ᴺQ. quámëa for purposes of Neo-Quenya, but given the meaning of its noun form I would assume its primary meaning is “✱nauseous”, as opposed to generally sick which would be [ᴺQ.] hlaiwa.