CREATE OR REPLACE SYNONYM syn_name_proc FOR my_schema.my_procedure@my_dblink;
CREATE OR REPLACE SYNONYM syn_name_pkg my_schema.my_package@my_dblink;
-- Call:
BEGIN
    syn_name_proc@my_dblink();                            -- procedure
    my_schema.syn_name_proc@my_dblink(param1, param2);    -- if parameters
    syn_name_pkg.my_proc@my_dblink();                    -- my_proc in a package
END;