jibber-jabbered

(/ˈdʒɪbə(ɹ)ˌdʒæbə(ɹ)d/)

adj.

Affected by alcohol to the point of impaired decision-making.

Zenya attempted to break a world record for the most marshmallows stuffed in their mouth, demonstrating their competitively jibber-jabbered side.

Source: Wiktionary