diff --git a/src/sphinx_autodoc_typehints/__init__.py b/src/sphinx_autodoc_typehints/__init__.py
index 6e68ee0..3eb0764 100644
--- a/src/sphinx_autodoc_typehints/__init__.py
+++ b/src/sphinx_autodoc_typehints/__init__.py
@@ -750,20 +750,31 @@ def _inject_signature(  # noqa: C901
             if app.config.typehints_defaults:
                 formatted_default = format_default(app, default, annotation is not None)
                 if formatted_default:
-                    if app.config.typehints_defaults.endswith("after"):
+                    type_annotation = _append_default(app, lines, insert_index, type_annotation, formatted_default)
 
-                        # advance index to the end of the :param: paragraph
-                        nlines = len(lines)
-                        i = insert_index
-                        while i < nlines and (lines[i + 1] == "" or lines[i + 1].startswith(" ")):
-                            i = i + 1
-
-                        lines[i] += formatted_default
+            lines.insert(insert_index, type_annotation)
 
-                    else:  # add to last param doc line
-                        type_annotation += formatted_default
 
-            lines.insert(insert_index, type_annotation)
+def _append_default(
+    app: Sphinx, lines: list[str], insert_index: int, type_annotation: str, formatted_default: str
+) -> str:
+    if app.config.typehints_defaults.endswith("after"):
+        # advance the index to the end of the :param: paragraphs
+        # (terminated by a line with no indentation)
+        # append default to the last nonempty line
+        nlines = len(lines)
+        i = insert_index + 1
+        j = insert_index  # last nonempty line
+        while i < nlines and (not lines[i] or lines[i].startswith(" ")):
+            if lines[i]:
+                j = i
+            i += 1
+        lines[j] += formatted_default
+
+    else:  # add to last param doc line
+        type_annotation += formatted_default
+
+    return type_annotation
 
 
 @dataclass
diff --git a/tests/test_integration_issue_384.py b/tests/test_integration_issue_384.py
index 83acef9..66815e6 100644
--- a/tests/test_integration_issue_384.py
+++ b/tests/test_integration_issue_384.py
@@ -4,7 +4,7 @@
 import sys
 from pathlib import Path
 from textwrap import dedent, indent
-from typing import TYPE_CHECKING, Any, Callable, Literal, NewType, TypeVar  # no type comments
+from typing import TYPE_CHECKING, Any, Callable, NewType, TypeVar  # no type comments
 
 import pytest
 
@@ -36,61 +36,42 @@ def dec(val: T) -> T:
 
 @expected(
     """\
-mod.function(x=5)
+mod.function(x=5, y=10, z=15)
 
    Function docstring.
 
    Parameters:
-      **x** ("int") -- optional specifier for how to handle complex
-      data types. See "ivy.func_wrapper.handle_complex_input" for more
-      detail.
-            
-   Returns:
-      something
+      * **x** ("int") -- optional specifier line 2 (default: "5")
 
-   Return type:
-      bytes
-""",
-)
-def function1(x: int, y: int, z: int) -> str:  # noqa: ARG001
-    """
-    Function docstring.
+      * **y** ("int") --
 
-    :param x: optional specifier for how to handle complex data types. See
-              ``ivy.func_wrapper.handle_complex_input`` for more detail.
-    :param y: another optional specifier for how to handle complex data types. See
-              ``ivy.func_wrapper.handle_complex_input`` for more detail.
+        another optional line 4
 
-    :param z: yet another optional specifier for how to handle complex data types. See
-              ``ivy.func_wrapper.handle_complex_input`` for more detail.
-    :return: something
-    :rtype: bytes
-    """
+        second paragraph for y (default: "10")
 
-@expected(
-    """\
-mod.function(x=5)
-
-   Function docstring.
+      * **z** ("int") -- yet another optional s line 6 (default: "15")
 
-   Parameters:
-      **x** ("int") -- optional specifier for how to handle complex
-      data types. See "ivy.func_wrapper.handle_complex_input" for more
-      detail.
-            
    Returns:
       something
 
    Return type:
       bytes
+
 """,
 )
-def function(x: int = 5, y: int = 10, z: int = 5) -> str:  # noqa: ARG001
+def function(x: int = 5, y: int = 10, z: int = 15) -> str:  # noqa: ARG001
     """
     Function docstring.
 
-    :param x: optional specifier 
+    :param x: optional specifier
               line 2
+    :param y: another optional
+              line 4
+
+              second paragraph for y
+
+    :param z: yet another optional s
+              line 6
 
     :return: something
     :rtype: bytes