I found that a solution of 2 parts water to 1 part rubbing alcohol and 1 part liquid detergent is effective for killing and driving the ants away, busting up their trail, and helps clean and disinfect. ealdthryth discovered the recipe for this online when she was looking for natural and non-toxic ways to deal with minor problems with ants.

Since we have 4 cats, we were concerned about using herbs and other natural repellents that would get rid of the ants without harming the cats as part of the bargain.