That’s what Eddie Sefko says here. Specifically:
They say Howard had a long night of partying on Jan. 19, the night after the Mavericks had won in Boston and less than 24 hours before playing the Wizards. The team officially said he missed the game against Washington on Jan. 20 with a stomach illness. But sources said team officials could not deny that it was a self-inflicted game off.
I would have liked to have seen how that would have shown up in the box score if everyone had been a little more forthright. “Josh Howard — DNP (booze flu).” And, b-t-dub, Howard is now back in my good graces.