diff --git a/starlette/middleware/base.py b/starlette/middleware/base.py
index d0089c0c9..b347a6a2d 100644
--- a/starlette/middleware/base.py
+++ b/starlette/middleware/base.py
@@ -27,7 +27,7 @@ async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None:
 
     async def call_next(self, request: Request) -> Response:
         loop = asyncio.get_event_loop()
-        queue: "asyncio.Queue[typing.Optional[Message]]" = asyncio.Queue(maxsize=1)
+        queue: "asyncio.Queue[typing.Optional[Message]]" = asyncio.Queue()
 
         scope = request.scope
         receive = request.receive