I think you're doing everything you can. Does he take a dummy?
I've been giving my dd meds many times a day since birth. . And I think it's so hard! What I do is lay dd on the bed or floor. . lean over her so her legs are in between my legs. .. She usually starts crying but that is my cue to squirt it in with her mouth open! Then shove a dummy in so she can't spit it out. It sounds crazy but it's only 10 seconds of unpleasantness! The dummy plus blowing in the face as pp said works a treat.
You can though try mixing it with the milk/bottle and maybe 20mls of milk if you think he'd drink it. You could try?
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