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What are the Side Effects of Caffeine?

Alex Paul
Alex Paul

The side effects of caffeine vary from person to person, with some people able to tolerate larger amounts of the substance. Caffeine doesn’t reduce the need to sleep, but it can prevent a person from feeling tired. One of the positive side effects of caffeine is that it can make certain drugs, such as painkillers, more effective. Other potential side effects include anxiety, irritability, diarrhea, and dizziness. If a large amount of caffeine is consumed over a period of time then addiction can occur, which leads to stronger and more unpleasant side effects.

One of the most noticeable side effects of caffeine is a reduced feeling of tiredness. Not only can this allow a person to stay awake for longer, but it has also been shown to increase athletic performance in some cases. The benefits of caffeine are short term though, and the effects usually wear off relatively quickly.

Energy drinks usually contain caffeine.
Energy drinks usually contain caffeine.

Caffeine is also known to increase the effectiveness of certain drugs. The substance may allow the body to absorb a drug quicker, which provides faster relief. For this reason, many painkillers include caffeine. It is also used with other drugs, including antihistamines, to counteract the feeling of fatigue induced by the medication.

There are a large number of other side effects of caffeine which may or may not affect an individual. The more severe symptoms usually occur only if someone has taken a large dose of caffeine, but others can appear as a result of smaller amounts. Some of the main side effects of caffeine include thirst, drowsiness, anxiety, irritability, confusion, and difficulty sleeping. Caffeine may also cause diarrhea and an increased need to urinate.

Addiction to caffeine can occur if a person consumes large amounts over a long period of time. Like most addictions, it is accompanied by a number of side effects. These include insomnia, peptic ulcers, heart palpitations, and constant headaches.

Constant headaches can accompany a caffeine addiction.
Constant headaches can accompany a caffeine addiction.

It is thought that caffeine may have an effect on learning. Initial studies have shown that if a person consumes caffeine in small amounts over a long period of time, it may lead to a slower rate of learning and a decreased long- term memory. There are, however, thought to be benefits to consuming caffeine, including an improvement in memory tasks. More research into the side effects of caffeine is needed to conclusively discover the benefits and risks of consuming the substance and at what levels it starts to negatively impact a person’s health.

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    • Energy drinks usually contain caffeine.
      By: lecostaloca
      Energy drinks usually contain caffeine.
    • Constant headaches can accompany a caffeine addiction.
      By: Subbotina Anna
      Constant headaches can accompany a caffeine addiction.
    • Heart palpitations are one possible side effect of caffeine.
      By: forestpath
      Heart palpitations are one possible side effect of caffeine.
    • Sodas typically contain caffeine.
      By: tiverylucky
      Sodas typically contain caffeine.