diff --git a/CHANGELOG.md b/CHANGELOG.md
index 77c0822..a67f797 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,8 @@
 ## 0.12.14
 
 * Add `containsOnce` matcher.
+* Deprecate `isCyclicInitializationError` and `NullThrownError`. These errors
+  will be removed from the SDK. Update them to catch more general errors.
 
 ## 0.12.13
 
diff --git a/lib/src/error_matchers.dart b/lib/src/error_matchers.dart
index df93d3e..5b6238d 100644
--- a/lib/src/error_matchers.dart
+++ b/lib/src/error_matchers.dart
@@ -15,8 +15,11 @@
 const isConcurrentModificationError =
     TypeMatcher<ConcurrentModificationError>();
 
-/// A matcher for [CyclicInitializationError].
-const isCyclicInitializationError = TypeMatcher<CyclicInitializationError>();
+/// A matcher for [Error].
+@Deprecated(
+    'CyclicInitializationError is deprecated and will be removed in Dart 3. '
+    'Use `isA<Error>()` instead.')
+const isCyclicInitializationError = TypeMatcher<Error>();
 
 /// A matcher for [Exception].
 const isException = TypeMatcher<Exception>();
@@ -27,8 +30,10 @@
 /// A matcher for [NoSuchMethodError].
 const isNoSuchMethodError = TypeMatcher<NoSuchMethodError>();
 
-/// A matcher for [NullThrownError].
-const isNullThrownError = TypeMatcher<NullThrownError>();
+/// A matcher for [TypeError].
+@Deprecated('NullThrownError is deprecated and will be removed in Dart 3. '
+    'Use `isA<TypeError>()` instead.')
+const isNullThrownError = TypeMatcher<TypeError>();
 
 /// A matcher for [RangeError].
 const isRangeError = TypeMatcher<RangeError>();
diff --git a/test/type_matcher_test.dart b/test/type_matcher_test.dart
index 306202c..99d4459 100644
--- a/test/type_matcher_test.dart
+++ b/test/type_matcher_test.dart
@@ -2,6 +2,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// ignore_for_file: deprecated_member_use_from_same_package
 import 'package:matcher/matcher.dart';
 import 'package:test/test.dart' show test, group;
 
@@ -11,7 +12,6 @@
   _test(isMap, {}, name: 'Map');
   _test(isList, [], name: 'List');
   _test(isArgumentError, ArgumentError());
-  // ignore: deprecated_member_use, deprecated_member_use_from_same_package
   _test(isCastError, TypeError());
   _test<Exception>(isException, const FormatException());
   _test(isFormatException, const FormatException());
@@ -20,13 +20,12 @@
   _test(isUnimplementedError, UnimplementedError('oops'));
   _test(isUnsupportedError, UnsupportedError('oops'));
   _test(isConcurrentModificationError, ConcurrentModificationError());
-  _test(isCyclicInitializationError, CyclicInitializationError());
+  _test(isCyclicInitializationError, Error());
   _test<NoSuchMethodError?>(isNoSuchMethodError, null,
       name: 'NoSuchMethodError');
-  _test(isNullThrownError, NullThrownError());
+  _test(isNullThrownError, TypeError());
 
   group('custom `TypeMatcher`', () {
-    // ignore: deprecated_member_use_from_same_package
     _test(const isInstanceOf<String>(), 'hello');
     _test(const _StringMatcher(), 'hello');
     _test(const TypeMatcher<String>(), 'hello');
@@ -56,9 +55,7 @@
 
 // Validate that existing implementations continue to work.
 class _StringMatcher extends TypeMatcher {
-  const _StringMatcher() : super(
-            // ignore: deprecated_member_use_from_same_package
-            'String');
+  const _StringMatcher() : super('String');
 
   @override
   bool matches(dynamic item, Map matchState) => item is String;