Hi MJC,
The only medicine I use to thicken everything up is 6-8 Loperamide a day which I find helps. I sometimes do use psyllium husk powder but find the loperamide does the trick. A toothpaste-like consistency is the best I can get. I also found codeine to work slightly better than loperamide but it has its downsides.
I was always told to stay away from too much fibre, and stick to starchy white bread, potato and pasta for thicker stools and I notice these foods do help.