Was bombarded by kitchen ants last year, they were coming from every kitchen crevis. Nothing I used helped and I tried some pretty expensive stuff. My daughter-in-law brought over a box of "Hot Shot MaxAttrax Ant Bait" A little plastic disc with an opening on one side. They come four in a pack and she said they were very inexpensive. I put one in a corner (out of sight). Haven't seen an ant since (over a year ago). I just got the box to give you the name of the product, it has three left in the box, I never put another one out - its still in the corner, probably not effective any longer but the ants must have passed the word to stay away from my kitchen. It was probably purchased to Walgreen's, CVS, Walmart, etc.
Good luck
PS Box says "guarenteed to work for even severe infestations, Kills in 24 Hours"