diff --git a/src/Control.Monad.Postgres.Cursor.purs b/src/Control.Monad.Postgres.Cursor.purs
index 6277c9e..83a0935 100644
--- a/src/Control.Monad.Postgres.Cursor.purs
+++ b/src/Control.Monad.Postgres.Cursor.purs
@@ -22,7 +22,6 @@ import Data.Tuple.Nested (type (/\), (/\))
 import Effect.Aff.Class (class MonadAff)
 import Effect.Aff.Unlift (class MonadUnliftAff)
 import Effect.Class (class MonadEffect, liftEffect)
-import Effect.Postgres.Error as E
 import Effect.Unlift (class MonadUnliftEffect)
 
 data Move
@@ -119,7 +118,7 @@ instance (MonadSession m) => MonadCursor (CursorT t m) t where
     RowsAffected n' <- query $ ("move relative $1 from " <> cur) /\ n
     pure n'
 
-instance (MonadThrow E.E m, MonadSession m) => MonadSession (CursorT t m) where
+instance (MonadSession m) => MonadSession (CursorT t m) where
   query = lift <<< query
   exec = lift <<< exec
   exec_ = lift <<< exec_
diff --git a/src/Control.Monad.Postgres.Session.purs b/src/Control.Monad.Postgres.Session.purs
index 324ca96..a0ac59b 100644
--- a/src/Control.Monad.Postgres.Session.purs
+++ b/src/Control.Monad.Postgres.Session.purs
@@ -2,7 +2,7 @@ module Control.Monad.Postgres.Session where
 
 import Prelude hiding (join)
 
-import Control.Monad.Error.Class (class MonadError, class MonadThrow, catchError, throwError)
+import Control.Monad.Error.Class (class MonadError, catchError, throwError)
 import Control.Monad.Fork.Class (class MonadBracket)
 import Control.Monad.Morph (hoist)
 import Control.Monad.Reader (ask)
@@ -44,7 +44,7 @@ instance MonadStartSession Client where
   endSession _ _ = pure unit
 
 -- | A monad representing a connected session to a database
-class (MonadThrow E.E m, MonadAff m) <= MonadSession m where
+class MonadAff m <= MonadSession m where
   -- | Executes a query and unmarshals the result into `r`
   query :: forall q r. AsQuery q => FromRows r => q -> m r
   -- | Executes a query and returns the number of rows affected