What does he give to his friend to drink?
Rashi: He gives wine. Seder Olam 28 applies this to Belshatzar, who gave to officers to drink from Klei ha'Mikdash. In them, they became drunk, angered Hashem, and were killed.
Radak: Nebuchadnetzar used to drink and get drunk, like we explained "v'Af Ki ha'Yayin Boged" (2:5). He used to give to drink to kings of the nations that he exiled; they were incarcerated in his house. When he wanted to drink and get drunk, also his colleague will; Re'ehu is like Re'av (his fellow kings). Also "Magen Giborehu" (Nachum 2:4, is like Giborav), "b'Hispalelo Ve'ad Re'ehu" (Iyov 42:10).
Radak citing Ibn Ezra: This is a Mashal. He gives to his friends to drink a cup of poison, and gets them drunk with his Chemes (flask). Radak ? it is correct to say that the verse is a Mashal, for the coming verse says "Tisov Alecha Kos Yemin Hashem."
Why does it say "Mesape'ach Chamasecha"?
Rashi: Via giving wine, he is Mesape'ach (adds to) his anger at him, and gets him drunk in his anger. He does all this in order to "Habit Al Me'oreihem" (refer to 2:15:4:1).
Radak: He stuck to them the flask 1 of wine, so they will drink constantly and get drunk. Mesape'ach is clinging, like "Sefacheni Na" (Shmuel I, 2:36), "Tachas Charul Yesufachu" (Iyov 30:7). Chamasecha is like "va'Yichlu ha'Mayim Min ha'Chemes"(Bereishis 21:15).
Malbim: "B'Chumam Ashis Es Mishteihem v'Hishkartim Lema'an Ya'alozu v'Yashnu Shenas Olam" (Yirmeyahu 51:39) explains this. When they started to drink from Klei ha'Mikdash, Hashem heated them greatly. After they became drunk, and slept forever. They did not hear the killing of Belshatzar and the coming of the army of Paras and Madai; the army killed them in their sleep, and they did not awaken. Via giving to them to drink, they were joined to your heat.
Radak: It is better to say that Chamasecha is an expression of Af and Chemah (anger), like "va'Ashakerem ba'Chamasi" (Yeshayah 63:6).
Why does it add "v'Af Shechar"?
Radak: He used to intoxicate them Bal Korcham (against their will), in order to mock them.
Malbim: They became very drunk.
What is the meaning of "Habit Al Me'oreihem"?
Rashi (from Shabbos 149b): It is looking at what is revealed - seeing their Ervah. This is Nebuchadnetzar, who gave wine to kings to drink. He intoxicated them, and sodomized them.
Rashi: Their disgrace was revealed. Their enemies saw their vileness.
Radak: The will become drunk and exposed, like happened to Noach ? "va'Yishkar va'Yisgal b'Soch Ahalo" (Bereishis 9:21). Me'oreihem is like Ervasam, even though they are different roots. Also from the root of Me'oreihem is "Peshotah v'Orah" (Yeshayah 32:11).
Malbim: Amidst great intoxication, they vomited the wine, and all saw their vomit.