Nicholas Brendon Nicholas Brendon

Buffy the Vampire Slayer's Nicholas Brendon apologized Monday for his "unacceptable behavior" in Boise, Idaho, which resulted in his arrest Friday evening.

The actor, 43, posted the apology on his Facebook account Monday morning and said he acted out after mixing prescription medication with alcohol and is intending to seek treatment for his "medical ailments" and "emotional demons."

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"I apologize. Usually those words end a message like this but I am beginning with them to emphasize how much I regret disappointing my family, my fans, and myself. I can offer an explanation but I make no excuse for my unacceptable behavior," he wrote.

"For the past 5 days, I have been taking prescription pain medication to help me manage a cyst behind my knee cap, which is scheduled for corrective surgery on Monday morning," he continued. "I made the poor decision to mix this prescribed medication with alcohol. The result was embarrassing and unacceptable."

Brendon was charged with two misdemeanors after witnesses reported a disturbance at the hotel where he was staying while in town for Tree City Comic Con.

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