My 2 year old son has little red dots starting on the back of his neck at the hairline and going down to his diaper line. It is continuing around to his chest and down his stomach. The dots are separate, not in clumps. What might this be? He hasn't had a fever, but he has vomited his juice up several times and is only picking at his food. He also had diarrehia this morning.

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Female , Age: 22

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benadryl gel