Giving a cat medicine - Tootsie tales

I've learned something new about giving a cat medicine. I've read a lot about people trying to wrangle cats, or trick cats, or outwit cats, or out-maneuver cats to give them needed medication. And, something that works for one cat, won't work for another, according to my reading. So, this is FYI, fwiw! Here's the deal: Tootsie has been suffering from some kind of respiratory infection since I got her from the shelter. On my first visit to the vet, a week after I brought her home, the vet gave me some liquid antibiotics. But Tootsie was so unhappy with the vet visit, she became really evasive. And, she is one strong and wiry cat. So, I waited a few days, and then the symptoms seemed to go away. So, in the interest of comity and getting her to trust me, I didn't give her the medication. But, suddenly last week the symptoms returned, and way worse than before. I discovered that the medication, which had been in the fridge, was discolored (label said do not use...