diff --git a/citext/__init__.py b/citext/__init__.py
index b9c4bd9..466ea28 100644
--- a/citext/__init__.py
+++ b/citext/__init__.py
@@ -12,6 +12,7 @@
 class CIText(types.Concatenable, types.UserDefinedType):
     # This is copied from the `literal_processor` of sqlalchemy's own `String`
     # type.
+    cache_ok = True
     def literal_processor(self, dialect):
         def process(value):
             value = value.replace("'", "''")
@@ -43,7 +44,10 @@ def process(value):
 
 def register_citext_array(engine):
     """Call once with an engine for citext values to be returned as strings instead of characters"""
-    results = engine.execute(sqlalchemy.text("SELECT typarray FROM pg_type WHERE typname = 'citext'"))
+    with engine.connect() as connection:
+        # Using engine.execute() is deprecated in SQLAlchemy >=1.4,<2, removed in >=2
+        # Using engine.connect().execute() is compatible with *all* SQLAlchemy >= 1.1 (and probably further back)
+        results = connection.execute(sqlalchemy.text("SELECT typarray FROM pg_type WHERE typname = 'citext'"))
     oids = tuple(row[0] for row in results)
     array_type = psycopg2.extensions.new_array_type(oids, 'citext[]', psycopg2.STRING)
     psycopg2.extensions.register_type(array_type, None)