If you’ve ever been behind the wheel of your vehicle and felt like you needed a little pick-me-up, you might have stopped to get some coffee or a soda. The caffeine in these beverages has the potential to wake you up a little bit, but the effects are short-lived.

Caffeine blocks the adenosine receptors in the brain, which means that the adenosine, which causes sleepiness, can’t make you feel tired. Unfortunately, caffeine doesn’t work for very long. As a result, someone who is drinking coffee to stay awake on the road may find that they’re soon driving while drowsy once again.

Did you know that caffeine can actually make you more tired than you were?

An interesting fact about caffeine is that it can make you feel drowsier than you were when you drank it. If you drink over three cups a day, the caffeine is more likely to make you dehydrated. This leads to drowsiness and dizziness. Additionally, while caffeine does work to block the adenosine receptors for a short time, it doesn’t actually stop the brain from producing the chemical.

As a result, the adenosine builds up in the brain. Once the receptors begin working again, you may feel tired and have that tiredness come on very quickly. That’s why caffeine is best used as a stopgap.

Caffeine’s effects don’t last long

Caffeine’s effects don’t last long, which is why it’s important to drink it only to keep yourself awake if you can soon pull over and rest. It only takes around 45 minutes for the chemical to be absorbed into the organs. The maximum length of time the effects of caffeine will last is six hours, but that depends on each person’s metabolism and their tolerance to caffeine.

Caffeine is not a cure for drowsiness. If a driver has been behind the wheel for many hours or is falling asleep behind the wheel, it’s better to stop and rest than to try to use caffeine to boost awareness. Getting good rest is the only real way to feel refreshed enough to drive safely enough to be aware of your surroundings.