What should I do for an allergic reaction in a cat?

I think my cat is having an allergic reaction to some medicine I got from the vet. I put some Lysine in her food (for a viral infection, sneezing) and now she has trouble swallowing and her right eye is runny. Will this run its course or is there something I should do today? Vet is closed on Sunday - can take her in first thing Monday (tomorrow). Just looking to see if there is anything I can do today.