diff --git a/src/js/simplemde.js b/src/js/simplemde.js
index 4c30e9c..2de43f3 100644
--- a/src/js/simplemde.js
+++ b/src/js/simplemde.js
@@ -1389,7 +1389,7 @@ 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