They're definitely well within the safe limits so far, and John doesn't seem to be reacting negatively to it. Ianto sets the water and cloth aside and fetches the little bottle and spoon again. Squeezing out another count of drops into it before carefully holding it out to the other man.

"Not too long. Here, try this," he offers. "I think we'd both prefer it if we could at least take the edge off of it before I start working on the worst of those gashes, yeah?"