diff --git a/AUTHORS b/AUTHORS
index de388e1..c29b373 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -5,3 +5,4 @@ licensing terms detailed in LICENSE.
 a license to everyone to use it as detailed in LICENSE.)
 
 M. Petra Baranski (info@progsource.de)
+Patrick José Pereira (patrickelectric@gmail.com)
diff --git a/docs/definitions.md b/docs/definitions.md
index a17e7bd..f93a380 100644
--- a/docs/definitions.md
+++ b/docs/definitions.md
@@ -221,10 +221,12 @@ results in
 
 ```
 **bold text**
+__bold text__
 ```
 results in
 ```html
 <strong>bold text</strong>
+<strong>bold text</strong>
 ```
 
 ## emphasized
diff --git a/include/maddy/strongparser.h b/include/maddy/strongparser.h
index cda6d21..c2dc441 100644
--- a/include/maddy/strongparser.h
+++ b/include/maddy/strongparser.h
@@ -30,9 +30,9 @@ public:
   /**
    * Parse
    *
-   * From Markdown: `text **text**`
+   * From Markdown: `text **text** __text__`
    *
-   * To HTML: `text <strong>text</strong>`
+   * To HTML: `text <strong>text</strong> <strong>text</strong>`
    *
    * @method
    * @param {std::string&} line The line to interpret
@@ -41,10 +41,16 @@ public:
   void
   Parse(std::string& line) override
   {
-    static std::regex re("(?!.*`.*|.*<code>.*)\\*\\*(?!.*`.*|.*<\\/code>.*)([^\\*\\*]*)\\*\\*(?!.*`.*|.*<\\/code>.*)");
+    static std::vector<std::regex> res
+    {
+      std::regex{"(?!.*`.*|.*<code>.*)\\*\\*(?!.*`.*|.*<\\/code>.*)([^\\*\\*]*)\\*\\*(?!.*`.*|.*<\\/code>.*)"},
+      std::regex{"(?!.*`.*|.*<code>.*)\\_\\_(?!.*`.*|.*<\\/code>.*)([^\\_\\_]*)\\_\\_(?!.*`.*|.*<\\/code>.*)"}
+    };
     static std::string replacement = "<strong>$1</strong>";
-
-    line = std::regex_replace(line, re, replacement);
+    for (const auto& re : res)
+    {
+      line = std::regex_replace(line, re, replacement);
+    }
   }
 }; // class StrongParser
 
diff --git a/tests/maddy/test_maddy_strongparser.cpp b/tests/maddy/test_maddy_strongparser.cpp
index ad70762..e054aa7 100644
--- a/tests/maddy/test_maddy_strongparser.cpp
+++ b/tests/maddy/test_maddy_strongparser.cpp
@@ -12,33 +12,87 @@
 
 TEST(MADDY_STRONGPARSER, ItReplacesMarkdownWithStrongHTML)
 {
-  std::string text = "some text **bla** text testing **it** out";
-  std::string expected = "some text <strong>bla</strong> text testing <strong>it</strong> out";
+  struct testIt
+  {
+    std::string text;
+    std::string expected;
+  };
+
+  std::vector<testIt> tests
+  {
+    {
+      "some text **bla** text testing **it** out",
+      "some text <strong>bla</strong> text testing <strong>it</strong> out"
+    },
+    {
+      "some text __bla__ text testing __it__ out",
+      "some text <strong>bla</strong> text testing <strong>it</strong> out"
+    },
+  };
+
   auto strongParser = std::make_shared<maddy::StrongParser>();
 
-  strongParser->Parse(text);
-
-  ASSERT_EQ(expected, text);
+  for (auto& test : tests)
+  {
+    strongParser->Parse(test.text);
+    ASSERT_EQ(test.expected, test.text);
+  }
 }
 
 TEST(MADDY_STRONGPARSER, ItReplacesEmphasizedMarkdownNotWithStrongHTML)
 {
-  std::string text = "some text *bla* text testing **it** out";
-  std::string expected = "some text *bla* text testing <strong>it</strong> out";
+  struct testIt
+  {
+    std::string text;
+    std::string expected;
+  };
+
+  std::vector<testIt> tests
+  {
+    {
+      "some text *bla* text testing **it** out",
+      "some text *bla* text testing <strong>it</strong> out"
+    },
+    {
+      "some text _bla_ text testing __it__ out",
+      "some text _bla_ text testing <strong>it</strong> out"
+    },
+  };
+
   auto strongParser = std::make_shared<maddy::StrongParser>();
 
-  strongParser->Parse(text);
-
-  ASSERT_EQ(expected, text);
+  for (auto& test : tests)
+  {
+    strongParser->Parse(test.text);
+    ASSERT_EQ(test.expected, test.text);
+  }
 }
 
 TEST(MADDY_STRONGPARSER, ItDoesNotParseInsideInlineCode)
 {
-  std::string text = "some text **bla** `/**text**/` testing `**it**` out";
-  std::string expected = "some text **bla** `/**text**/` testing `**it**` out";
+  struct testIt
+  {
+    std::string text;
+    std::string expected;
+  };
+
+  std::vector<testIt> tests
+  {
+    {
+      "some text **bla** `/**text**/` testing `**it**` out",
+      "some text **bla** `/**text**/` testing `**it**` out",
+    },
+    {
+      "some text _bla_ text testing __it__ out",
+      "some text _bla_ text testing <strong>it</strong> out"
+    },
+  };
+
   auto strongParser = std::make_shared<maddy::StrongParser>();
 
-  strongParser->Parse(text);
-
-  ASSERT_EQ(expected, text);
+  for (auto& test : tests)
+  {
+    strongParser->Parse(test.text);
+    ASSERT_EQ(test.expected, test.text);
+  }
 }