diff --git a/CHANGELOG b/CHANGELOG
index f9d5797a2..77180751f 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -19,6 +19,8 @@ NEXT
   CWD outside a test package pytest would get fixture discovery wrong.
   Thanks to Wolfgang Schnerring for figuring out a reproducable example.
 
+- Introduce pytest_enter_pdb hook (needed e.g. by pytest_timeout to cancel the
+  timeout when interactively entering pdb).
 
 2.6.2
 -----------
diff --git a/_pytest/hookspec.py b/_pytest/hookspec.py
index 5a4466388..6d1420740 100644
--- a/_pytest/hookspec.py
+++ b/_pytest/hookspec.py
@@ -262,3 +262,5 @@ def pytest_exception_interact(node, call, report):
     that is not an internal exception like "skip.Exception".
     """
 
+def pytest_enter_pdb():
+    """ called upon pdb.set_trace()"""
diff --git a/_pytest/pdb.py b/_pytest/pdb.py
index 607a4582b..d0f7509f9 100644
--- a/_pytest/pdb.py
+++ b/_pytest/pdb.py
@@ -42,6 +42,7 @@ class pytestPDB:
             tw = py.io.TerminalWriter()
             tw.line()
             tw.sep(">", "PDB set_trace (IO-capturing turned off)")
+            self._pluginmanager.hook.pytest_enter_pdb()
         pdb.Pdb().set_trace(frame)
 
 
diff --git a/testing/test_pdb.py b/testing/test_pdb.py
index 2cc0727b0..cc1f1e10e 100644
--- a/testing/test_pdb.py
+++ b/testing/test_pdb.py
@@ -267,3 +267,21 @@ class TestPDB:
             "*NameError*xxx*",
             "*1 error*",
         ])
+
+    def test_enter_pdb_hook_is_called(self, testdir):
+        testdir.makeconftest("""
+            def pytest_enter_pdb():
+                print 'enter_pdb_hook'
+        """)
+        p1 = testdir.makepyfile("""
+            import pytest
+
+            def test_foo():
+                pytest.set_trace()
+        """)
+        child = testdir.spawn_pytest(str(p1))
+        child.expect("enter_pdb_hook")
+        child.send('c\n')
+        child.sendeof()
+        if child.isalive():
+            child.wait()