diff --git a/sentry_sdk/utils.py b/sentry_sdk/utils.py
index a6ece4faf1..ef6989208c 100644
--- a/sentry_sdk/utils.py
+++ b/sentry_sdk/utils.py
@@ -1736,7 +1736,7 @@ def match_regex_list(
         return False
 
     for item_matcher in regex_list:
-        if not substring_matching and item_matcher[-1] != "$":
+        if not substring_matching and (not item_matcher or item_matcher[-1] != "$"):
             item_matcher += "$"
 
         matched = re.search(item_matcher, item)