diff --git a/skimage/io/_io.py b/skimage/io/_io.py
index 54769edc..eb704a6f 100644
--- a/skimage/io/_io.py
+++ b/skimage/io/_io.py
@@ -248,7 +248,7 @@ def show():
 
     >>> for i in range(4):
     ...     io.imshow(np.random.random((50, 50)))
-    >>> io.show()
+    >>> io.show() # doctest: +SKIP
 
     '''
     return call_plugin('_app_show')
diff --git a/skimage/viewer/viewers/core.py b/skimage/viewer/viewers/core.py
index 8b5eb7ba..ad3bfcc9 100644
--- a/skimage/viewer/viewers/core.py
+++ b/skimage/viewer/viewers/core.py
@@ -73,7 +73,7 @@ class ImageViewer(QtGui.QMainWindow):
     >>> from skimage import data
     >>> image = data.coins()
     >>> viewer = ImageViewer(image)
-    >>> # viewer.show()
+    >>> viewer.show() # doctest: +SKIP
 
     """