diff --git a/dist/perfect-scrollbar.js b/dist/perfect-scrollbar.js
index 0f8e4b5..89ef62e 100644
--- a/dist/perfect-scrollbar.js
+++ b/dist/perfect-scrollbar.js
@@ -576,10 +576,10 @@
     let scrollBy = null;
 
     function mouseMoveHandler(e) {
-      const y = e.touches && e.touches[0] ? e.touches[0].pageY : e[pageY];
+      const py = e.touches && e.touches[0] ? e.touches[0].pageY : e[pageY];
 
       element[scrollTop] =
-        startingScrollTop + scrollBy * (y - startingMousePageY);
+        startingScrollTop + scrollBy * (py - startingMousePageY);
       addScrollingClass(i, y);
       updateGeometry(i);
 
diff --git a/src/handlers/drag-thumb.js b/src/handlers/drag-thumb.js
index b953088..66ecbfc 100644
--- a/src/handlers/drag-thumb.js
+++ b/src/handlers/drag-thumb.js
@@ -53,10 +53,10 @@ function bindMouseScrollHandler(
   let scrollBy = null;
 
   function mouseMoveHandler(e) {
-    const y = e.touches && e.touches[0] ? e.touches[0].pageY : e[pageY];
+    const py = e.touches && e.touches[0] ? e.touches[0].pageY : e[pageY];
 
     element[scrollTop] =
-      startingScrollTop + scrollBy * (y - startingMousePageY);
+      startingScrollTop + scrollBy * (py - startingMousePageY);
     addScrollingClass(i, y);
     updateGeometry(i);