If he hasn't been in the tray since you took the litter out I'd put it back in, even if it's just a thin layer. Cats are creatures of habit, they don't like things changed about.

To test for fleas, use a flea comb to comb through the fur, especially around the neck, under arms and base of tail, and then wipe the combings onto wet kitchen paper. Flea dirt will show blood stains when you wet it.

If you ever do find any, spray bedding, and then wash it thoroughly, and treat carpets , especially around the perimeter, fleas are more likely to lay eggs around the edges than in the middle.

When he gets to 6 mnths you can worm three monthly with drontal tablets or talk to your vet about spot on flea/worm treatments. I think the spot ons can be used younger than 6 mnths, but not sure whether you would use them monthly like the panacur.

__________________