diff --git a/dist/showdown.js b/dist/showdown.js
index bdd07a8..347c643 100644
Binary files a/dist/showdown.js and b/dist/showdown.js differ
diff --git a/dist/showdown.js.map b/dist/showdown.js.map
index b9c2fd7..6d6808f 100644
Binary files a/dist/showdown.js.map and b/dist/showdown.js.map differ
diff --git a/dist/showdown.min.js b/dist/showdown.min.js
index ea2f7b5..8dfa6b0 100644
Binary files a/dist/showdown.min.js and b/dist/showdown.min.js differ
diff --git a/dist/showdown.min.js.map b/dist/showdown.min.js.map
index 3f1838a..b1c38ab 100644
Binary files a/dist/showdown.min.js.map and b/dist/showdown.min.js.map differ
diff --git a/src/subParsers/makehtml/underline.js b/src/subParsers/makehtml/underline.js
index ad7f654..a3d4414 100644
--- a/src/subParsers/makehtml/underline.js
+++ b/src/subParsers/makehtml/underline.js
@@ -8,11 +8,17 @@ showdown.subParser('makehtml.underline', function (text, options, globals) {
   text = globals.converter._dispatch('makehtml.underline.before', text, options, globals).getText();
 
   if (options.literalMidWordUnderscores) {
-    text = text.replace(/\b_?__(\S[\s\S]*)___?\b/g, function (wm, txt) {
+    text = text.replace(/\b___(\S[\s\S]*?)___\b/g, function (wm, txt) {
+      return '<u>' + txt + '</u>';
+    });
+    text = text.replace(/\b__(\S[\s\S]*?)__\b/g, function (wm, txt) {
       return '<u>' + txt + '</u>';
     });
   } else {
-    text = text.replace(/_?__(\S[\s\S]*?)___?/g, function (wm, m) {
+    text = text.replace(/___(\S[\s\S]*?)___/g, function (wm, m) {
+      return (/\S$/.test(m)) ? '<u>' + m + '</u>' : wm;
+    });
+    text = text.replace(/__(\S[\s\S]*?)__/g, function (wm, m) {
       return (/\S$/.test(m)) ? '<u>' + m + '</u>' : wm;
     });
   }
diff --git a/test/functional/makehtml/cases/features/underline/simple.html b/test/functional/makehtml/cases/features/underline/simple.html
index 51756cf..1f8e5ae 100644
--- a/test/functional/makehtml/cases/features/underline/simple.html
+++ b/test/functional/makehtml/cases/features/underline/simple.html
@@ -2,3 +2,4 @@
 <p><u>an underlined sentence</u></p>
 <p><u>three underscores are fine</u></p>
 <p>_single_ underscores are left alone</p>
+<p><u>multiple</u> underlines in a <u>paragraph</u></p>
\ No newline at end of file
diff --git a/test/functional/makehtml/cases/features/underline/simple.md b/test/functional/makehtml/cases/features/underline/simple.md
index cc96921..510be1f 100644
--- a/test/functional/makehtml/cases/features/underline/simple.md
+++ b/test/functional/makehtml/cases/features/underline/simple.md
@@ -5,3 +5,5 @@ __an underlined sentence__
 ___three underscores are fine___
 
 _single_ underscores are left alone
+
+__multiple__ underlines in a __paragraph__
\ No newline at end of file