Hi! Congrats on trying to introduce a new cat into your home and family!
MOST IMPORTANT is PATIENCE!! It takes time. Some cats hide for the first two weeks and only come out at night to eat and use the litter box. Some cats adjust quickly, others need more time. There is no ONE RULE that always applies but if you follow the suggestions below as best you can you have a much, much better chance of success.
Generally speaking it does not work well to throw two previously unacquainted cats together and expect they will get along. Here are some tips for introducing a new cat safely and successfully:
Ok, so you will need some supplies 🙂
Go to your local hardware store (or any hardware store!) and buy the LARGE size adjustable window screen—should be about 2 feet square. You will use this after the first few days to block the kitties from each other but allow them to see each other.
Litter pan and litter for new cat (if cat has been fostered, try to get some used–but clean!–litter to make transition to a new box easier)
Can of plain pumpkin (kitty’s tummies can get tricky when they are stressed and a tsp or two of pumpkin in their wet food makes a huge difference– and it’s cheap)
It’s best if you can get someone else to bring New Cat (NC) into your apt. If the foster or rescue organization cannot bring NC to you have a friend meet you outside your apt and have them bring the carrier in. If you have a spare room for him to chill in during his stay, great. If not, use your bathroom! The idea is to allow the cats to smell each other but not see or touch one another for the first week or so. For the first few days keep the door closed–I put the window screen up as well so I can enter and exit without risk of escape—if you have an animal gate or can get one (Wag.com delivers in, like, 24 hrs!) that works too! Get the tallest one you can find bc cats do jump 🙂
For the first few days spend some time w NC when you feed him. Don’t be alarmed if he hides behind the toilet or wherever, this is new to him, too. When you are not with NC lavish attention upon your kitty but basically act like nothing has changed. Don’t be alarmed if your cat hisses a little at the bathroom door or sits staring at it—he is just trying to figure out what’s what.
Take a sock and rub it on each cat’s cheek and then place your kittys sock near NC’s food dish and vice versa—they will start to associate the other cats smell with good things. Also give your kitty treats by the bathroom door (or wherever NC is) so he associates NC’s smell with treats.
Opening the door. This phase allows the cats to see each other where before they have only smelled each other. They may hiss gently or meowl or even growl a little bit. Close the door or throw a towel over the gate to relieve their stress when this happens. Gradually increase the time they are exposed to each other. Give lots of treats to each cat and if possible FEED them in separate bowls on each side of the gate. Do this for a few days.
Phase 3 is when they first have full access to each other. Have toys and a spray bottle (set to mist, not jet!) handy in case they are stressed out and tussling. Cats can play pretty rough—things to look out for as alarms are super puffy tails, ears back, and fur flying! But if they start to seem a little stressed a great thing to do it to start playing with a toy (I like those large crinkly foil balls–or you can make some nifty cat toys yourself and try to involve them both in the play—tossing it between them, using a ribbon between them, etc. Stay calm and allow them limited access at first, then increase.
Kitty and human bliss 🙂
Cats have glands in their cheeks that produce pheromones. When a cat rubs its cheek against your leg or furniture, these secretions promote comfort and well being. Pheromones are similar to a glandular pen pal. You can set up a scent exchange by brushing the cats with the same brush, trading blankets or towels, or even using synthetic pheromone Feliway® spray or plug-in products which help relieve excitably. Feliway spray and diffusers are THE BOMB. They are expensive but waaay worth it.
From Last Hope Animal Rescue:
For several days rotate rooms, giving each cat contingent a chance to inspect the lair of the other. This way the newcomer gets to explore the whole house while rubbing his facial calling card on strategic spots. Feed the cats (still separate) tasty wet food in each area. Cats are like men- the way to their heart is through their stomachs.
The process can take days to weeks depending on the cat dynamics. There will probably be some hissing and spitting. If a huge ruckus erupts, distract them; then praise them when it’s calm. Do not rush things. If a cat runs away to hide, do not force close encounters. Even if progress is made, monitor all mingling for the first few weeks. When no one is home, the new cat should stay in his “safe room”.
Your patience may well pay off. Some cats eventually become soul mates. Your cats may never be best buddies; some, like Garbo, rather be alone; others merely tolerate each other. When you think about it, there is nothing wrong with peaceful co-existence, either the feline or the human kind.