Get stuck in toilet with individual snorting bit of Dexedrine (3,4)
I believe the answer is:
bog down
'get stuck' is the definition.
(synonyms)
'toilet with individual snorting bit of dexedrine' is the wordplay.
'toilet' becomes 'bog' (informal term for toilet).
'with' says to put letters next to each other.
'individual' becomes 'own'.
'snorting' is an insertion indicator (snort can mean to ingest through the nose).
'bit of' says to take the initial letters.
The initial letter of 'dexedrine' is 'd'.
'bog'+'own'='bogown'
'bogown' enclosing 'd' is 'BOG-DOWN'.
'in' acts as a link.
(Other definitions for bog down that I've seen before include "Encumber (with work, etc)" , "Impede" , "Encumber, hinder" .)