Them

Ant traps. We had that problem a few years ago, and we have a friend whose business it is to keep pests out of restaurants. He brought us a whole bag of ant traps. Within a few days, the ants were gone. But you do have to live with them for a few days because what they do us bring the poison back to the queen, which ultimately kill the whole colony. Ugh. I hope the torture is over soon.

There is a liquid product called "Ant Rid". You just squeeze a couple drops ( almost like consistency of honey) where the ants are walking and then watch them take it back to their nest. It safe and it always works for me. But make sure it's the liquid stuff not the 'sand' one.

Being in the country, we use to get ants every summer. Now we don't get any.

Borax, a natural mineral, sprinkled where the ants like to walk will kill off the infestation. It's fairly safe for pets (cats and dogs can eat small amounts without any adverse effect), but I would do more research if you have young kids in the home. The ants track it back to their home on their feet where it becomes toxic to them. It's also a great cleaning product, so if you can't sprinkle it, you can make a wonderful kitchen scrub with the borax and a bit of water that will disinfect and have almost the same success rate as powdered borax does with ants.

Another thing that really helped us was switching to unscented cleaners. Citrus and fruit scents really attracted the ants, so the more I cleaned, the more they came back.

The only other thing is to find out what they are eating. They aren't wood ants are they, cause that's a sign that there's something wrong with your home. If they are eating sugar, maybe try keeping it in the freezer till they are gone.

My parents have this problem; whenever we visit we eventually encounter trails of ants. My mother insists that killing them non-chemically (vacuum cleaner or whatever) only brings more. She uses the spray...

Ants come in two types...one that loves fat..and other that love water. The fat loving ants like soap in the bathroom..along with the water lovers that like water. Boric acid can help..or remove their trails with a bleach solution--which is just a holding measure. All the 'natural' stuff has failed for me...you really need baseboard sprays or ant bait along the entry points to solve it. Water loving ants don't care for ant bait..you have to put down a barrier.
I doubt they're really coming up through the drain...but seem that way as the drain is a water supply (for lovers) and a fat supply (with soaps in the drain) for fat lovers.

Ha ha - yep I woke up this morning to find ants crawling across my pillow. On the counter I can handle, but in my bed?! At least they aren't cockroaches. Disturbing as they may be, I don't think there are any health risks. Now I am curious about the sonar thing...

https://www.youtube.com/watch?v=wM1DgihKHVI
I know that they really don't like orange oil- as in the oil derived from the rind of the citrus fruit. I'd get several lbs of oranges, juice them and run the peels through the garbage disposal several times a day. Sometimes when you think only a something strong enough to kill an elephant would work, simpler things do help. You can find orange oil spray online too,just make sure it is not a synthetic smell.

Wait… Wouldn't entering via a sink or bath drain mean they'd have to swim past the p-trap? What kind of ants are those??? Forget the gel and run! Defend yourself with your kitchen torch!

I get ants around my cat bowls once or twice a year. I use fipronil - it doesn't kill them instantly & is non-repellant so they drag it back to the nest and it ends up killing lots of them. A single application on their trail almost always works for me. It's the active ingredient in the Frontline flea control product, and I know it's reasonably safe around pets.

Raid Ant Gel has been like a miracle for us. I've always hated spraying poison around my kitchen. A dab about the size of a match head near their entry point is all it takes. Mine come in from behind the garbage disposal switch so I pry up the cover plate and squeeze a little back there and that's the last ant I'll see for the "season".

I know what you are going through, last year I was infested, it seemed like millions of ants everywhere not just my kitchen, They even infiltrated my freezer and refrigerator. What a mess!! Like summer of eggplant I tried every natural method including a "green exterminator" nothing worked. A friend told me to get Ortho home defense ant bait traps, I placed them where I thought the ants might be coming from and after a few days they diminished and a week later they were gone. I have pets so spraying for me was not an option, the traps can be placed in out of the way places that cannot be accessed by pets or children, I feel your pain and hope your ant infestation disappears.

Do you have a garbage disposal connected to your sink drain?

Pierno - This happens to us every spring. I have tried every non-chemical method out there but I find that spraying an anti-ant spray (like Bengal) aggressively (3x a day) around the entire perimeter of the kitchen at the baseboards and other less well sealed joints + ant traps in key locations (for us it's under the sink, near the garbage & by the window) is all I can do to keep them away. Coming through the drains sounds strange. I have also used a monthly pest service as well but did not find that the $ = what was gained.

I feel your pain. I had that problem in my previous place, and it didn't get solved until I bought one of those sonar thingys that you plug into the wall and it emits some kind of ethereal sound humans can't hear. Then and only then did they all march off with the Pied Piper...