Yes that sounds like unusual behaviour - but not necessarily due to the drugs.
Are these carpet/fibrous tiles or hard stone/clay? What are they cleaned with? I remember you referring to underfloor heating...is it switched on?
Unless he's trying to soothe irritation on his tongue (eg from fungal?) then it sounds like some type of "frustrated foraging"......i.e. he is looking for a particular type of nutritional source and can't find it.
If this happened to one of my poorly pigs, I would lay out a piggy buffet in small amounts on the tiles...not just what he eats regularly but all manner of weird and wonderful other things to try and find out what it is he wants......
a) coarse fibre: torn strips of kitchen roll/newspaper, inner cardboard tube, wood shavings (yes - some of my poorly pigs eat shavings)
b) Salt water(v small amount), diarolyte, osteocare...;........for sodium and potassium ions, minerals inc Calcium
c) metatone tonic - Vit B/K, Orange juice - Vit C
d) fresh grass, plantain and dandelion leaves
e) fresh basil (antiseptic), parsley and coriander
f) fresh silver birch leaves (still green not brown - good for urinary issues appraently)
g) fresh melon
h) dried herbage but spread out thinly including readigrass/hays
i) normal poops
My own urinary pigs have developed "fads" - mainly for coarse fibre and minerals/ions.........and in some but not all cases, some of the fresh natural forage listed above.....they seem to know what they need to get better...we just have to help them access it!
I know it's a bit "out of the box" but it's worked for me before!
x