diff --git a/racket/collects/db/private/sqlite3/ffi.rkt b/racket/collects/db/private/sqlite3/ffi.rkt
index f876eed5c8..cb0ac1d351 100644
--- a/racket/collects/db/private/sqlite3/ffi.rkt
+++ b/racket/collects/db/private/sqlite3/ffi.rkt
@@ -82,7 +82,8 @@
               (ptr-add sql-buffer (c-string-length sql-buffer))))
 
 (define-sqlite sqlite3_prepare
-  (_fun (db sql) ::
+  (_fun #:blocking? #t
+        (db sql) ::
         (db : _sqlite3_database)
         (sql-buffer : _gcpointer = (trim-and-copy-buffer sql))
         ((c-string-length sql-buffer) : _int)
@@ -93,7 +94,8 @@
                                          (not (points-to-end? tail sql-buffer))))))
 
 (define-sqlite sqlite3_prepare_v2
-  (_fun (db sql) ::
+  (_fun #:blocking? #t
+        (db sql) ::
         (db : _sqlite3_database)
         (sql-buffer : _gcpointer = (trim-and-copy-buffer sql))
         ((c-string-length sql-buffer) : _int)
@@ -181,7 +183,8 @@
 ;; ----------------------------------------
 
 (define-sqlite sqlite3_step
-  (_fun _sqlite3_statement -> _int))
+  (_fun #:blocking? #t
+        _sqlite3_statement -> _int))
 
 (define-sqlite sqlite3_column_type
   (_fun _sqlite3_statement _int -> _int))