It's 6.30 am, you have to be at work in two hours and you discover that you are out of coffee.
Do you a) shrug your shoulders knowing you can a cup at work, b) leave the house feeling like you're not quite yourself or c) throw a huge tantrum and contemplate calling in sick?
If it's C, you may be suffering from caffeine use disorder.
New research suggests that 50% of regular caffeine consumers have had difficulty quitting or reducing caffeine use, with some even suffering withdrawal symptoms in their attempt to cut the coffee.
The Caffeine Use Disorder: A Comprehensive Review and Research Agenda study, co-authored by American University psychology professor Laura Juliano, found that the common belief that caffeine isn't hard to give up might be incorrect.
Caffeine is the most used drug in the world; it can be found in tea, coffee, soft drinks, chocolate and pain relief medication.
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Caffeine In Drinks
Despite this, health expects have been slow to acknowledge the detrimental affect that high levels of caffeine consumption can have. The American Psychiatric Association officially recognised Caffeine Use Disorder as a health concern in need of further research just last year.
This latest study, published in the Journal of Caffeine Research, was co-authored by Steven Meredith and Roland Griffiths of the Johns Hopkins University School of Medicine and John Hughes from the University of Vermont.
It used previous caffeine-related research to look for biological proof of caffeine dependence, data that indicated how prevalent dependence is, and physical or psychological symptoms experienced by caffeine users.
Research uncovered that users had difficulty quitting caffeine even if advised to in the event of a medical condition such as a heart condition, pregnancy or bleeding disorder.
"The negative effects of caffeine are often not recognised as such because it is a socially acceptable and widely consumed drug that is well integrated into our customs and routines," Juliano said.
"And while many people can consume caffeine without harm, for some it produces negative effects, physical dependence, interferes with daily functioning, and can be difficult to give up, which are signs of problematic use."
Current research advises coffee drinkers to limit their consumption to no more than 400 mg per day, approximately the equivalent of two to three cups of coffee, 200mg for pregnant women or those with health problems.
Juliano said: "Genetics research may help us to better understand the effects of caffeine on health and pregnancy as well as individual differences in caffeine consumption and sensitivity.'
According to the study, those suffering genuine addiction were willing to undergo treatment to combat the problem.