"Don't take these everyday, only when you need them".

"Don't take these everyday, only when you need them".  A longterm insomnia habit - when everyone is focused on preventing exactly this?

These innocent words, uttered by millions of responsible medical practitioners worldwide, can unknowingly, inadvertently, trigger a powerful reward schedule that combines with the features of normal sleep to create longterm insomnia. Ironically, while intended to improve sleep and prevent medication dependence.

The BEACH study on prescribing data shows this: 90% of Australians who present with insomnia return from their GPs with a hypnotic prescription, with 50% of these scripts being Temazepam, the recommended insomnia hypnotic. Over a 20 year period 174 million benzodiazepine scripts were recorded, with per-script WHO-defined daily doses steadily increasing since 1998. And again, Temazepam the most-dispensed benzodiazepine over the 20 year period. That's a lot of insomnia.

How does this habit-that's-woke-to-habit-formation-dangers happen?

The starting point is the odd sleepless night, a normal feature of our sleep evolution.  The brain's 2 survival tasks are 1) to get us the sleep we need, 2) keep us alert for danger.  Guess which one must be prioritised? Yep, alertness for danger; you can stay up all night listening for a predator which turns out to be a branch scratching the window.

But don't underestimate the brain's capacity to "grab" sleep around the need to stay alert for danger.  Even if that "danger" is: "my stupid brain can't do sleep!" And Homeostatic sleep pressure builds over waking hours, so you can't resist it for more than a few days before falling asleep. 

So here is the insomnia paradox:  Yearning for sleep but trusting it less.  

You may not believe this but research findings suggest actual sleep duration isn't significantly less in insomnia sufferers compared to "good" sleepers. But insomnia clients RECALL night-time waking periods too well compared to "good" sleepers.  

Here's where prescription sleep medications come in.  Hypnotic medications (benzodiazepines, Z-drugs) and even the new Orexin receptor antagonist medication Suvorexant (Merck), come with manufacturer warnings about memory loss.  Well, these are the very therapeutic features that insomnia clients seek (without realising).  Recalling your nightly waking periods too well makes any substance that can block new memory the default go-to.

The most commonly used hypnotic medications can deliver dose-related anterograde amnesia and sedation which mercifully feels like deep sleep for as long as the effect lasts.  Sleep expert Allison Harvey (UC Berkeley University) states sedation is not sleep.  But the recall that counts to users is of the feeling of deep sleep. This is of course positively reinforcing, so we will tend to medicate more.

Already an attribution shift has begun towards trusting the medications rather than drug-free sleep, because in insomnia we already distrust the brain's "unreliable" sleep self-regulation enough to take the medications in the first place. 

All the essential features of habit formation are in place: a cue (insomnia), plus an action (taking the medication) plus a reward (amnesia & sedation that looks like deep sleep).  Malcolm Lader of Kings College Addiction Research Centre describes the "difficulty in preventing short term (benzodiazepine) use from extending indefinitely with the risk of dependence".

Unfortunately using the medications every day now means drug tolerance develops, so they are less effective than before.  Our threat-scanning process reasserts itself. Insomnia (on the nights the drug's not used, or even the nights it is used but doesn't work) engages the brain's alertness system. This is still part of normal homeostatic drive; under threat we can ignore our circadian clock & stay awake half the night building sleep pressure. This is seen as aversive, and confirms our belief that our brain can't "do" sleep but the medication can.

Good sleeps are now seen as only intermittent prizes despite the layering-up of sleep aids.  When we humans can't predict when the next "good sleep" is coming, despite all all the sleep aids & early nights, this is a frustrating threat to us.

Either we start ad hoc self-medicating to try to increase the sedation & guarantee the sleep (risking accidental overdose) or we see the tolerance development has cost us and try to undo it.  This means: saving up the medications for the 2 or 3 nights a week we absolutely MUST sleep (eg Sunday nights before the working week) and re-sensitising to the medication by not using it for 4-5 nights per week.

This takes a lot of calculating: is Sunday night more medication-worthy than Tuesday night because of the meeting Wednesday morning?  Ideally to re-sensitise more you'd just take it Sunday night and no other night, for maximum therapeutic effect.

And what is calculating but frontal lobe activity? Perfectly designed to keep you awake another night if your homeostatic drive allows it.  

All the conscientious insomnia clients try to get to sleep without medications - until the desperation peaks at 1am ("I should try to sleep on my own first, or maybe I need it tonight? It's getting late: I have to decide soon. Big meeting tomorrow. But I've already used it once this week!").  No wonder insomnia clients dread bedtime.  The stakes are high when you doubt sleep and yet demand more from it.  

And on it goes, chronic insomnia, chronic doubt and cost-benefit calculations and ongoing heroic attempts at responsible use and drug re-sensitisation. Was Thoreau prefiguring this when he wrote "The mass of men lead lives of quiet desperation"?

The careful and sparingly-taken insomnia pill-use habit around intermittent sleep rewards is manna from heaven for hypnotic pharmaceutical manufacturers.  Even if clients use them less often, they may likely use them for much longer.  Investors, take note.