diff --git a/litellm/proxy/guardrails/guardrail_hooks/ibm_guardrails/ibm_detector.py b/litellm/proxy/guardrails/guardrail_hooks/ibm_guardrails/ibm_detector.py
index 72e0b3f013..c61ef3334c 100644
--- a/litellm/proxy/guardrails/guardrail_hooks/ibm_guardrails/ibm_detector.py
+++ b/litellm/proxy/guardrails/guardrail_hooks/ibm_guardrails/ibm_detector.py
@@ -127,13 +127,9 @@ class IBMGuardrailDetector(CustomGuardrail):
         headers = {
             "Authorization": f"Bearer {self.auth_token}",
             "content-type": "application/json",
+            "detector-id": self.detector_id,
         }
 
-        query_params = {"detector_id": self.detector_id}
-
-        # update the api_url with the query params
-        self.api_url = f"{self.api_url}?{urlencode(query_params)}"
-
         verbose_proxy_logger.debug(
             "IBM Detector Server request to %s with payload: %s",
             self.api_url,
diff --git a/scripts/mock_ibm_guardrails_server.py b/scripts/mock_ibm_guardrails_server.py
index 9850b62747..a9251c14ce 100644
--- a/scripts/mock_ibm_guardrails_server.py
+++ b/scripts/mock_ibm_guardrails_server.py
@@ -234,8 +234,8 @@ async def root():
 
 @app.post("/api/v1/text/contents")
 async def text_detection(
-    detector_id: str,  # query parameter
     request: TextDetectionRequest,
+    detector_id: str = Header(None),  # query parameter
     authorization: Optional[str] = Header(None),
 ):
     """
@@ -243,6 +243,7 @@ async def text_detection(
 
     Args:
         request: Detection request with content and detector ID
+        detector_id: ID of detector
         authorization: Bearer token for authentication
 
     Returns: