Master Cleanse Forum - Master Cleanser Lemonade Diet

I need to have a cavity filled. I've been having toothaches so I need to see my dentist asap. He won't be back in town until maybe a couple pf weeks from now, but i was planning to start the mc on the first. He'll probably need to inject me with novicain. Can anyone think of any reason this might be a bad/dangerous idea to be on novicain and the mc at the same time, even if it's only for a day?