What does the cryptic crossword clue "Drug I’ll fake for Dutch old money (8)" mean?

The definition is "old money". The wordplay uses an anagram. anagram of DRUG ISLE = GUILDERS; definition: "old money" The answer is GUILDERS.

Drug I’ll fake for Dutch old money (8)

Guardian Cryptic #29657 | 16 Down | 2025-04-01 flower