diff --git a/jedi/evaluate/finder.py b/jedi/evaluate/finder.py
index ad2a6c33..2e841c99 100644
--- a/jedi/evaluate/finder.py
+++ b/jedi/evaluate/finder.py
@@ -388,15 +388,11 @@ def _eval_param(evaluator, param, scope):
             and func.instance.is_generated and str(func.name) == '__init__':
         param = func.var.params[param.position_nr]
 
-    # Add pep0484 type hints
+    # Add pep0484 and docstring knowledge.
     pep0484_hints = pep0484.follow_param(evaluator, param)
-    if pep0484_hints:
-        return pep0484_hints
-
-    # Add docstring knowledge.
     doc_params = docstrings.follow_param(evaluator, param)
-    if doc_params:
-        return doc_params
+    if pep0484_hints or doc_params:
+        return list(set(pep0484_hints) | set(doc_params))
 
     if isinstance(param, ExecutedParam):
         return res_new | param.eval(evaluator)
diff --git a/test/completion/pep0484.py b/test/completion/pep0484.py
index 6a7ce6ce..b9ab88aa 100644
--- a/test/completion/pep0484.py
+++ b/test/completion/pep0484.py
@@ -7,7 +7,13 @@ class A():
     pass
 
 
-def function_parameters(a: A, b, c: str, d: int=4):
+def function_parameters(a: A, b, c: str, d: int, e: str, f: str, g: int=4):
+    """
+    :param e: if docstring and annotation agree, only one should be returned
+    :type e: str
+    :param f: if docstring and annotation disagree, both should be returned
+    :type f: int
+    """
     #? A()
     a
     #?
@@ -16,6 +22,12 @@ def function_parameters(a: A, b, c: str, d: int=4):
     c
     #? int()
     d
+    #? str()
+    e
+    #? int() str()
+    f
+    # int()
+    g
 
 
 def return_unspecified():