![]() These effects include mild CNS stimulation and wakefulness, ability to sustain intellectual activity, and decreased reaction times.Ĭaffeine is rapidly and completely absorbed in humans, with 99 percent being absorbed within 45 minutes of ingestion (Bonati et al., 1982 Liguori et al., 1997). The pharmacological effects of caffeine are similar to those of other methylxanthines (including those found in various teas and chocolates). This wide range in the plasma mean half-life of caffeine is due to both innate individual variation, and a variety of physiological and environmental characteristics that influence caffeine metabolism (e.g., pregnancy, obesity, use of oral contraceptives, smoking, altitude). However, caffeine's elimination half-life may range between 1.5 and 9.5 hours, while the total plasma clearance rate for caffeine is estimated to be 0.078 L/h/kg (Brachtel and Richter, 1992 Busto et al., 1989). The mean half-life of caffeine in plasma of healthy individuals is about 5 hours. Structurally, caffeine (and the other methylxanthines) resembles the purines. ![]() In pure form, it is a bitter white powder. This chapter provides a brief summary of the metabolism and physiological effects of caffeineĬaffeine (1,3,7-trimethylxanthine) is a plant alkaloid with a chemical structure of C 8H 10N 4O 2 (see Figure 2–1) and a molecular weight of 194.19. It has numerous pharmacological and physiological effects, including cardiovascular, respiratory, renal, and smooth muscle effects, as well as effects on mood, memory, alertness, and physical and cognitive performance. Timeshifter will tell you when you could benefit from using caffeine during your trips to get the maximum benefits, and when to avoid caffeine to avoid disrupting your sleep.As stated in Chapter 1, caffeine is the most widely used central nervous system (CNS) stimulant in the world. Caffeine is too powerful for children, and their small size increases the relative dose compared to adults and so caffeine should not be given to children.Įnjoying caffeine at the right time can help increase your energy level while traveling, but caffeine at the wrong time can negatively impact your sleep quality and may reduce your ability to sleep. Using caffeine “little and often”, and then stopping it as long as possible before bed, will optimize the benefits of caffeine and minimize the negative effects on sleep. Having caffeine in your body at bedtime will have a negative effect on your sleep that night. It typically has a half-life of three to five hours so if you take 100mg of caffeine at 10am, you will still have 12.5mg of caffeine in your system at bedtime 12 hours later. Caffeine stays in our system for a long time. As a result, caffeine is a highly effective stimulant. Caffeine is an adenosine-receptor antagonist and therefore blocks the sleepiness-inducing effects of adenosine. Adenosine is part of the sleep regulation system, and is associated with increased sleepiness. A by-product of this energy use is an increase in the amount of adenosine in our bodies. ![]() Work out the caffeine content of your typical drink so you can plan how much to have. Brewed ‘drip’ coffee and energy drinks tend to have very high amounts of caffeine so only half a cup of these is needed every two hours. Enjoying caffeine 8 hours or less before bedtime will negatively impact your sleep quality.įor those travelers who want to use caffeine, Timeshifter provides advice on when and how to use it, and when to avoid it, to support the light-dark and sleep schedule that will reset your clock quickly.Ĭaffeine is present in tea, coffee, caffeinated sodas, chocolate, and in some pain medications. More than that will not make you more alert but may reduce your ability to sleep later. When you're tired while traveling, a cup of caffeinated tea or coffee, or a caffeinated soda (equivalent to about 50mg of caffeine) every two hours should help you stay awake.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |