StanleyPain Tom Baker was not drunk nor known for being drunk. He's just a very odd man and he loved playing with people's minds and expectations of him. When you watch Dr. Who you have to understand that he was like this with pretty much everyone he worked with.
Desidiosus Tom Baker is certainly odd, but it's well known he likes his alcohol.
However, unlike you or I or other mere mortals it has no effect on him whatsoever.