I Never recommend using Drano. Well, ONLY if the drain is running slow and only on the bathtub drain and the bathroom sink drain because it can work on hair.
With that Being said, you have to call the plumber. Otherwise, if the water is standing still and not draining, it can damage the washers and connections on the plumbing (Drano has Harsh Chemicals).
Back to your question. I would say just water. (PLENTY of Soap and water) if the residue is in the sink and/or around the drain (Basket strainer, pop-up assembly, etc..).
If you meant, maybe that it didn’t unclog the drain, and you have some standing in the sink. Make sure to use nitrile gloves when and if the Chemicals need to be removed.
Because these chemicals can actually. Burn your hands; if so, just run a lot of water over them.
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