The most common and most likely answer to this crossword clue is the 6 plus 4 letter word GREEDY GUTS
I've seen this crossword clue in The Times
G
R
E
E
D
Y
G
U
T
S
More clues leading to the result GREEDY GUTS
- Guzzler sounding high after opening gallon bottle
- Guzzler decided to avoid opening variable bottle
- A glutton, Stu baked goods earlier including piping
- Pig comes up to sandwiches daintily at first, guy flummoxed
- Gets endless grub, ye’d fancy
- Pig mixture of dry egg and suet
- Glutton welcomes embracing start of diet — funny guy!
- Get drug? Yes, if desperate glutton
- Dry egg mixed with suet for pig
Buddy explains!

The straight part
We know that "Guzzler" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case guzzler = greedy guts.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.