On Whether to Prefer Pain to Pass

Most of us are "time-biased" in preferring pains to be past rather than future and pleasures to be future rather than past. However, it turns out that if you are risk averse and time-biased, then you can be turned into a "pain pump" -in order to insure yourself against misfortune, you will take a series of pills which leaves you with more pain and better off in no respect. Since this vulnerability seems rationally impermissible, while time-bias and risk aversion seem rationally permissible, we are left with a puzzle.