diff --git a/src/js/simplemde.js b/src/js/simplemde.js
index 016d693..2317389 100644
--- a/src/js/simplemde.js
+++ b/src/js/simplemde.js
@@ -1354,7 +1354,7 @@ function SimpleMDE(options) {
 
 
 	// Merging the promptTexts, with the given options
-	options.promptTexts = promptTexts;
+	options.promptTexts = extend({}, promptTexts, options.promptTexts || {});
 
 
 	// Merging the blockStyles, with the given options