Insomnia and Caffeine

This chapter describes a male pharmacist who self-treated his tendency to severe sleepiness with very high doses of caffeine in the form of brewed coffee. This resulted in his presentation to clinicians with the complaint, not of hypersomnia, but with insomnia and sleep deprivation. His clinical presentation and sleep studies are reviewed in detail. The pharmacology of caffeine is briefly reviewed, including the use of caffeine as the most common psychoactive substance in the world today, and specifically, the effects of caffeine on sleep morphology, duration, and quality. The quality of sleep is altered by caffeine with effects dependent on the timing of consumption, the amount consumed, and individual differences in sensitivity; thus assessment of consumption is necessary in any patient presenting with insomnia. Large doses of caffeine produce a vicious cycle of nocturnal sleep deprivation producing more excessive daytime sleepiness and even greater caffeine consumption.