Give him a long warm soak. I'm sure it well just pass.
The bigger problem is finding out how he got it and making sure he can't get it again.
Are you letting him roam your house? If so, that is a big no. They need their own proper enclosure both inside and out and that's where they should be visited and enjoyed, in their own enclosures, not the floors of your home. If he doesn't roam your house then someone is guilty of giving it to him