diff --git a/extensions/markdown/syntaxes/markdown.tmLanguage b/extensions/markdown/syntaxes/markdown.tmLanguage
index 26a48c15d3e..bb0e0c36761 100644
--- a/extensions/markdown/syntaxes/markdown.tmLanguage
+++ b/extensions/markdown/syntaxes/markdown.tmLanguage
@@ -3318,7 +3318,7 @@
 				<dict>
 					<key>begin</key>
 					<string>(?x)
-								(\*|_)(?=\S)								# Open
+							\b(\*|_)(?=\S)								# Open
 								(?=
 									(
 										&lt;[^&gt;]*+&gt;							# HTML tags
@@ -3368,7 +3368,7 @@
 						</dict>
 					</dict>
 					<key>end</key>
-					<string>(?&lt;=\S)(\1)((?!\1)|(?=\1\1))</string>
+					<string>(?&lt;=\S)(\1)((?!\1)|(?=\1\1))\b</string>
 					<key>name</key>
 					<string>markup.italic.markdown</string>
 					<key>patterns</key>
diff --git a/extensions/markdown/syntaxes/markdown.tmLanguage.base b/extensions/markdown/syntaxes/markdown.tmLanguage.base
index ca8b920a22f..442b45acce8 100644
--- a/extensions/markdown/syntaxes/markdown.tmLanguage.base
+++ b/extensions/markdown/syntaxes/markdown.tmLanguage.base
@@ -808,7 +808,7 @@
 				<dict>
 					<key>begin</key>
 					<string>(?x)
-								(\*|_)(?=\S)								# Open
+							\b(\*|_)(?=\S)								# Open
 								(?=
 									(
 										&lt;[^&gt;]*+&gt;							# HTML tags
@@ -858,7 +858,7 @@
 						</dict>
 					</dict>
 					<key>end</key>
-					<string>(?&lt;=\S)(\1)((?!\1)|(?=\1\1))</string>
+					<string>(?&lt;=\S)(\1)((?!\1)|(?=\1\1))\b</string>
 					<key>name</key>
 					<string>markup.italic.markdown</string>
 					<key>patterns</key>