Okay, the user wants me to translate "react excessively" into Japanese. Let me think about the right term here. "React" in this context is probably about responding or acting, so "反応する" or "行動する" could work. "Excessively" means to a greater degree than is normal or appropriate. So, maybe "過剰に" or "過度に" would be good adverbs.
Putting it together, "過剰に反応する" or "過度に行動する" seem possible. But I should check if there's a more natural phrase. Sometimes "overreact" is translated as "過剰反応する" which is a common expression. So "過剰反応する" might be the most accurate and natural translation here. Let me confirm that. Yes, that's a standard way to say "react excessively" in Japanese. Alright, I'll go with that.