The idiom "pissed as a newt" is commonly used to describe someone who is extremely drunk. However, there are several synonyms that can also be used in place of this expression. One of the most popular replacements is "hammered" which means to be completely intoxicated. "Blitzed" is another term that can be used to describe someone who is heavily under the influence of alcohol. "Sloshed" and "looped" are also good alternatives for "pissed as a newt." These words can be used in a variety of contexts to describe someone who has had too much to drink and is exhibiting symptoms of drunkenness.