diff --git a/optional-requirements.txt b/optional-requirements.txt
index dd4f9878..5aac831b 100644
--- a/optional-requirements.txt
+++ b/optional-requirements.txt
@@ -1,34 +1,34 @@
 # GDrive Integration
-google-api-python-client==1.7.11
-gevent>=1.2.1
-greenlet>=0.4.12
-httplib2>=0.9.2
-oauth2client>=4.0.0
-uritemplate>=3.0.0
-pyasn1-modules>=0.0.8
-pyasn1>=0.1.9
-PyDrive>=1.3.1
+google-api-python-client==1.7.11,<1.8.0
+gevent>=1.2.1,<1.5.0
+greenlet>=0.4.12,<0.5.0
+httplib2>=0.9.2,<0.18.0
+oauth2client>=4.0.0,<4.14.0
+uritemplate>=3.0.0,<3.1.0
+pyasn1-modules>=0.0.8,<0.3.0
+pyasn1>=0.1.9,<0.5.0
+PyDrive>=1.3.1,<1.14.0
 PyYAML>=3.12
-rsa==3.4.2
-six==1.10.0
+rsa==3.4.2,<4.1.0
+six>=1.10.0,<1.14.0
 
 # goodreads
-goodreads>=0.3.2
-python-Levenshtein>=0.12.0
+goodreads>=0.3.2,<0.4.0
+python-Levenshtein>=0.12.0,<0.13.0
 
 # ldap login
-python_ldap>=3.0.0
-flask-simpleldap>1.3.0
+python_ldap>=3.0.0,<3.3.0
+flask-simpleldap>1.3.0,<1.5.0
 
 #oauth
 flask-dance>=0.13.0
-sqlalchemy_utils>=0.33.5
+sqlalchemy_utils>=0.33.5,<0.37.0
 
 # extracting metadata
-lxml>=3.8.0
-Pillow>=4.0.0
+lxml>=3.8.0,<4.6.0
+Pillow>=4.0.0,<7.1.0
 rarfile>=2.7
 
 # other
-natsort>=2.2.0
+natsort>=2.2.0,<7.1.0
 git+https://github.com/OzzieIsaacs/comicapi.git@ad8bfe5a1c31db882480433f86db2c5c57634a3f#egg=comicapi
diff --git a/requirements.txt b/requirements.txt
index daf2538d..bec3a1d4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,15 +1,15 @@
-Babel>=1.3
-Flask-Babel>=0.11.1
-Flask-Login>=0.3.2
-Flask-Principal>=0.3.2
-singledispatch>=3.4.0.0
+Babel>=1.3, <2.9
+Flask-Babel>=0.11.1,<1.1.0
+Flask-Login>=0.3.2,<0.5.1
+Flask-Principal>=0.3.2,<0.5.0
+singledispatch>=3.4.0.0,<3.5.0.0
 backports_abc>=0.4
-Flask>=1.0.2
-iso-639>=0.4.5
-PyPDF2==1.26.0
+Flask>=1.0.2,<1.2.0
+iso-639>=0.4.5,<0.5.0
+PyPDF2==1.26.0,<1.27.0
 pytz>=2016.10
-requests>=2.11.1
-SQLAlchemy>=1.1.0
-tornado>=4.1
-Wand>=0.4.4
-unidecode>=0.04.19
+requests>=2.11.1,<2.23.0
+SQLAlchemy>=1.1.0,<1.4.0
+tornado>=4.1,<6.1
+Wand>=0.4.4,<0.6.0
+unidecode>=0.04.19,<1.2.0