diff --git a/RELEASE_NOTES.txt b/RELEASE_NOTES.txt
index e9cce587b..354514ef3 100644
--- a/RELEASE_NOTES.txt
+++ b/RELEASE_NOTES.txt
@@ -1,6 +1,10 @@
 Changes since 4.3.1
 -------------------
 
+* [HTTPCLIENT-1442] Authentication header set by the user gets removed in case
+  of proxy authentication (affects plan HTTP requests only).
+  Contributed by Oleg Kalnichevski <olegk at apache.org>
+
 * [HTTPCLIENT-1441] Caching AsynchronousValidationRequest leaks connections.
   Contributed by Dominic Tootell <dominic.tootell at gmail.com>
 
diff --git a/httpclient/src/main/java/org/apache/http/impl/execchain/MainClientExec.java b/httpclient/src/main/java/org/apache/http/impl/execchain/MainClientExec.java
index be8a2e0c5..7c88effe1 100644
--- a/httpclient/src/main/java/org/apache/http/impl/execchain/MainClientExec.java
+++ b/httpclient/src/main/java/org/apache/http/impl/execchain/MainClientExec.java
@@ -293,8 +293,13 @@ public CloseableHttpResponse execute(
                         }
                     }
                     // discard previous auth headers
-                    request.removeHeaders(AUTH.WWW_AUTH_RESP);
-                    request.removeHeaders(AUTH.PROXY_AUTH_RESP);
+                    final HttpRequest original = request.getOriginal();
+                    if (!original.containsHeader(AUTH.WWW_AUTH_RESP)) {
+                        request.removeHeaders(AUTH.WWW_AUTH_RESP);
+                    }
+                    if (!original.containsHeader(AUTH.PROXY_AUTH_RESP)) {
+                        request.removeHeaders(AUTH.PROXY_AUTH_RESP);
+                    }
                 } else {
                     break;
                 }