I had a one spot fox face rabbit fish exhibit the same symptoms. I had him in a QT because of an outbreak of ich, and possibly velvet. I did a 50% water change and put in Seachem Cupramine (per instructions), and this fixed the issue. There was no outward sign of disease on the fish, so I put it down to the parasite being in his gills. He's absolutely fine now.
Point to note: if you use Cupramine, check their web site for dosing instructions. The bottle and web site instructions do differ, and I contacted them about which was correct. Apparently, they have changed their guidance, so it depends on how old the bottle is you purchase. But, the web site has the correct dosage instructions.
Good luck with the wrasse!