diff --git a/consumer.go b/consumer.go
index 4777356..e28fe67 100644
--- a/consumer.go
+++ b/consumer.go
@@ -299,10 +299,10 @@ func (c *Consumer) getShardIterator(ctx context.Context, streamName, shardID, se
 }
 
 func isRetriableError(err error) bool {
-	switch err.(type) {
-	case *types.ExpiredIteratorException:
+	if oe := (*types.ExpiredIteratorException)(nil); errors.As(err, &oe) {
 		return true
-	case *types.ProvisionedThroughputExceededException:
+	}
+	if oe := (*types.ProvisionedThroughputExceededException)(nil); errors.As(err, &oe) {
 		return true
 	}
 	return false