diff --git a/lib/index.js b/lib/index.js
index 06dd7493..8ac7d8bb 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -119,7 +119,7 @@ function HttpProxyMiddleware(context, opts) {
         if (pathRewriter) {
             var path = pathRewriter(req.url, req);
 
-            if (path !== false) {
+            if (typeof path === 'string') {
                 req.url =  path;
             } else {
                 logger.info('[HPM] pathRewrite: No rewritten path found. (%s)', req.url);