diff --git a/wkhtmltopdf/tests/tests.py b/wkhtmltopdf/tests/tests.py
index c9f2187..ad0f7cd 100644
--- a/wkhtmltopdf/tests/tests.py
+++ b/wkhtmltopdf/tests/tests.py
@@ -59,6 +59,13 @@ def test_options_to_args(self):
                                           file_name='file-name'),
                          ['--file-name', 'file-name',
                           '--heart', u'♥'])
+        self.assertEqual(_options_to_args(
+            custom_header='Authentication mytoken',
+            cookie='key1 value1'),
+            ['--cookie', 'key1', 'value1',
+             '--custom-header', 'Authentication', 'mytoken'])
+        with self.assertRaises(ValueError):
+            _options_to_args(custom_header='Authentication')
 
     def test_wkhtmltopdf(self):
         """Should run wkhtmltopdf to generate a PDF"""
diff --git a/wkhtmltopdf/utils.py b/wkhtmltopdf/utils.py
index 68034b8..2ff4548 100644
--- a/wkhtmltopdf/utils.py
+++ b/wkhtmltopdf/utils.py
@@ -46,6 +46,7 @@
                        '--enable-toc-back-links', '--footer-line', '--no-footer-line',
                        '--header-line', '--no-header-line', '--disable-dotted-lines',
                        '--disable-toc-links', '--verbose']
+MULTI_VALUE_OPTIONS = ['--custom-header', '--cookie', '--post', '--replace']
 
 
 def _options_to_args(**options):
@@ -60,12 +61,18 @@ def _options_to_args(**options):
         formatted_flag = '--%s' % name if len(name) > 1 else '-%s' % name
         formatted_flag = formatted_flag.replace('_', '-')
         accepts_no_arguments = formatted_flag in NO_ARGUMENT_OPTIONS
+        is_multi_value_option = formatted_flag in MULTI_VALUE_OPTIONS
         if value is None or (value is False and accepts_no_arguments):
             continue
         flags.append(formatted_flag)
         if accepts_no_arguments:
             continue
-        flags.append(six.text_type(value))
+        if is_multi_value_option:
+            k, v = value.split(maxsplit=1)
+            flags.append(six.text_type(k))
+            flags.append(six.text_type(v))
+        else:
+            flags.append(six.text_type(value))
     return flags