diff --git a/src/subParsers/images.js b/src/subParsers/images.js
index 0dc6b04..8dde87b 100644
--- a/src/subParsers/images.js
+++ b/src/subParsers/images.js
@@ -41,6 +41,7 @@ showdown.subParser('images', function (text, options, globals) {
     }
 
     altText = altText.replace(/"/g, '"');
+    altText = showdown.helper.escapeCharacters(altText, '*_', false);
     url = showdown.helper.escapeCharacters(url, '*_', false);
     var result = '<img src="' + url + '" alt="' + altText + '"';