Maybe, but I doubt it.) Scissors will work to cut out the big mats, but what you'll really want to do is use clippers to give the kitteh a buzz cut.
Just get rid of all the long fur, and let the cat start over.
My dog gets seasonal contact dermatitis right around this time of year and the vet recommends 1 benedryl.
It's 50 sheckles well spent to take him to the vet and let them sedate and trim him. (She crys about it but doesn't try to hurt you or get away.) However, if she were truly scared and could become nasty, 50 bucks seems like the right amount.
We do what we can, but he takes it for about five minutes with the scissors and clippers before he loses his mind. Though (being a cheap person), I would probably keep a few pairs of scissors around and snip while giving lovies.
One person restrains kitteh, one person deals with the fur.
Options for restraining kitteh include rolling the cat in a big towel (like a feline burrito) to keep the legs swaddled, or kneeling with your shins on the floor and squatting on the cat (where your body weight is all in your thighs on your heels - you're not squashing the cat, you're using your calves and thighs to physically hem it in).
Keep in mind that the entirety of the mats do not have to be dealt with at once. - purplehorseshoe, who's had two long-haired Maine Coons Hammer.
Seriously, our cat Bob is an outdoor cat and gets really severely matted.
I don't want to knock her out, just loopy enough to lay still for about ten minutes. I would suck it up and pay the ish to get her professionally groomed.
My departed Bernie developed severe matting problems as she aged - her fur was fine and kinky and she couldn't bathe herself overly well. Sometimes animals have bad reactions, and it seems an unnecessary risk to take with an animal you don't know well.
My question is: Are there any safe OTC sedatives for cats? I asked my vet for a sedative and he told he that I had to come back. I believe my Vet is a good professional, but I simply cannot afford any more medical care for them.