diff --git a/docs/useSearchParam.md b/docs/useSearchParam.md
index f1184676..6d9fe29c 100644
--- a/docs/useSearchParam.md
+++ b/docs/useSearchParam.md
@@ -2,7 +2,6 @@
 
 React sensor hook that tracks browser's location search param.
 
-
 ## Usage
 
 ```jsx
@@ -27,3 +26,7 @@ const Demo = () => {
   );
 };
 ```
+
+## Caveats/Gotchas
+
+When using a hash router, like `react-router`'s [`<HashRouter>`](https://github.com/ReactTraining/react-router/blob/master/packages/react-router-dom/docs/api/HashRouter.md), this hook won't be able to read the search parameters as they are considered part of the hash of the URL by browsers.