diff --git a/litellm/integrations/otel/plumbing/context.py b/litellm/integrations/otel/plumbing/context.py
index 57e220815b5..1282e654365 100644
--- a/litellm/integrations/otel/plumbing/context.py
+++ b/litellm/integrations/otel/plumbing/context.py
@@ -26,6 +26,7 @@ if TYPE_CHECKING:
     from litellm.integrations.otel.model.destination import OtelDestination
 
 _PROPAGATOR: Final = TraceContextTextMapPropagator()
+_W3C_TRACE_HEADERS: Final = frozenset(("traceparent", "tracestate"))
 
 # The request's root span — the FastAPI-owned SERVER span — captured ONCE when the
 # proxy first resolves it, so request-level spans (the LLM call, guardrails) can
@@ -334,7 +335,9 @@ def inject_trace_context(headers: Mapping[str, str], parent_span: object = None)
     context: Final = _outgoing_trace_context(parent_span)
     if context is None:
         return dict(headers)  # mutable-ok: OpenTelemetry propagator requires a mutable carrier
-    carrier: Final = dict(headers)  # mutable-ok: OpenTelemetry propagator requires a mutable carrier
+    carrier: Final = {  # mutable-ok: OpenTelemetry propagator requires a mutable carrier
+        key: value for key, value in headers.items() if key.lower() not in _W3C_TRACE_HEADERS
+    }
     _PROPAGATOR.inject(carrier, context=context)
     return carrier
 
diff --git a/tests/test_litellm/integrations/otel/test_otel_v2_components.py b/tests/test_litellm/integrations/otel/test_otel_v2_components.py
index 43546241d06..72f6213e880 100644
--- a/tests/test_litellm/integrations/otel/test_otel_v2_components.py
+++ b/tests/test_litellm/integrations/otel/test_otel_v2_components.py
@@ -507,6 +507,26 @@ def test_inject_trace_context_uses_ambient_span_without_request_root():
     assert propagated.get_span_context().span_id == ambient.get_span_context().span_id
 
 
+def test_inject_trace_context_replaces_stale_trace_headers():
+    def run():
+        tracer = _test_tracer()
+        with tracer.start_as_current_span("ambient") as ambient:
+            headers = {
+                "Traceparent": "00-" + "a" * 32 + "-" + "b" * 16 + "-01",
+                "Tracestate": "vendor=old",
+                "x-keep": "1",
+            }
+            result = ctx_mod.inject_trace_context(headers)
+            propagated = get_current_span(TraceContextTextMapPropagator().extract(result))
+            return result, ambient, propagated
+
+    result, ambient, propagated = ContextVarContext().run(run)
+    assert sum(key.lower() == "traceparent" for key in result) == 1
+    assert not any(key.lower() == "tracestate" for key in result)
+    assert result["x-keep"] == "1"
+    assert propagated.get_span_context().trace_id == ambient.get_span_context().trace_id
+
+
 def test_inject_trace_context_prefers_explicit_parent_span_over_root_and_ambient():
     def run():
         tracer = _test_tracer()