Have you tried crushing a pill between 2 teaspoons and mixing it with
their favourite food?  Otis's kidney tablets are yeast flavoured, I
give him one every evening with his dinner and he always eats it, I
just put a small amount of food down to make sure he gets all the pill,
then he can have his "seconds".  Mind you, I have never had a problem
giving him his insulin shots either, I do it while he's eating, he's
such a docile old softie (apart from when I take him to TED that is!)
He's also very food-centric so this makes life easier.  I remember
before I realised that leaving the cat carrier out all the time with a
nice cushion in it meant that he'd use it as one of his sleeping places
and thus not freak out when it came out of the cupboard, I used to put
a trail of biscuits (no longer allowed) going into the box and waited
for him to get in the box to get the last biscuit and then shut the
door (quickly to avoid me losing a finger), that only worked a couple
of times though before he got wise!

Marcia