diff --git a/requirements.txt b/requirements.txt
index 435c81c..1d6c4f9 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,7 +6,7 @@ google-api-python-client==1.7.11
 google-auth==1.11.2
 google-auth-httplib2==0.0.3
 gunicorn==20.0.4
-httplib2==0.18.0
+httplib2==0.19.0
 icalendar==4.0.4
 itsdangerous==1.1.0
 Jinja2==2.11.1