"Sleep Deprivation Is a Surprisingly Effective Way To Treat Depression"

"If you’re healthy and you don’t sleep, you’ll feel in a bad mood. But if you’re depressed, it can prompt an immediate improvement in mood, and in cognitive abilities. But, Benedetti adds, there’s a catch: once you go to sleep and catch up on those missed hours of sleep, you’ll have a 95 per cent chance of relapse... 

A handful of American studies had suggested that lithium might prolong the effect of sleep deprivation, so they investigated that. They found that 65 percent of patients taking lithium showed a sustained response to sleep deprivation when assessed after three months, compared to just 10 per cent of those not taking the drug.

Since even a short nap could undermine the efficacy of the treatment, they also started searching for new ways of keeping patients awake at night, and drew inspiration from aviation medicine, where bright light was being used to keep pilots alert... 

“When people are seriously depressed, their circadian rhythms tend to be very flat; they don’t get the usual response of melatonin rising in the evening, and the cortisol levels are consistently high rather than falling in the evening and the night,” says Steinn Steingrimsson, a psychiatrist at Sahlgrenska University Hospital in Gothenburg, Sweden, who is currently running a trial of wake therapy.

Recovery from depression is associated with a normalization of these cycles. “I think depression may be one of the consequences of this basic flattening of circadian rhythms and homeostasis in the brain,” says Benedetti. “When we sleep-deprive depressed people, we restore this cyclical process.”... 

The bias towards pharmaceutical solutions has kept chronotherapy below the radar for many psychiatrists. “A lot of people just don’t know about it,” says Veale."

https://tonic.vice.com/en_us/article/yw59bv/sleep-deprivation-is-a-surprisingly-effective-way-to-treat-depression

I have experienced this; when I only get 5 hours of sleep, I'm sometimes confusingly functional. I used to think that maybe it was because that's all the sleep I got some nights in high school and college and so my brain became accustomed to being productive in that state. But I also realize that I can only stay sleep deprived for a few days before the negatives outweigh the positives. So it's a balance.