sleep debt 

lack of sleep, or when you owe yourself some rest becasue you have been too busy.

when you are not getting enough sleep, and need to calculate how much you owe your body

sleep account is negative, or in the red

first used by British airways
and also sited on multiple occasions by lifehacker.com

i've been gathering some serious sleep debt since i have started pulling these all-nighters on a regular basis.

sleep debt by Jesse Colburn March 4, 2008

sleep debt 

Something you accumulate whenever you don't sleep an adequate amount on a given night. In the ghetto they call it "slizzeep to da dizzebt".

If sleep debt was dollars, yo' mama would be a rich bitch.

sleep debt by Nick D March 17, 2003

Sleep Debt 

The quantification of sleep debt.

If you're tired you probably have sleep debt.

Sleep Debt by SevenWest April 8, 2019

Sleep Debt Loan Sharks 

The forces that usually plague a person after he or she acquires a considerable sleep debt by sleeping very little (or not at all) for extended periods of time.

Sleep debt loan sharks may use schemes such as spontaneous microsleep, low cognitive capabilities, and (if the sleep debt is extraordinarily high) auditory and visual hallucinations, in order to make a person pay off his or her sleep debt.

As with regular loan sharks, sleep debt loan sharks can be staved off temporarily. In this case, it is through the use of psychostimulants, such as caffeine, amphetamines, ecstasy, cocaine, etc.

Edwin: Hey man, how 'bout you n' me go clubbin' tonight?

Godfrey: Nah man, them sleep debt loan sharks be keepin' me down. Gotta get me some sleep n' sh*t befo' I get real f*cked up.

Edwin: Yo man, two words: Coffee, biotch!

Sleep Debt Loan Sharks by Double A Tron April 3, 2011