Is caffeine dangerous?

Caffeine has a powerful effect on the body. It can boost energy and alertness, which explains why some people can’t start their day without a cup of coffee.

As long as you drink it in moderation, caffeine isn’t dangerous. Most people can safely consume up to 400 milligrams of caffeine a day. (That’s about four 8-ounce cups of coffee.) But other people are more sensitive to caffeine. If they consume too much, they may experience:

  • restlessness
  • insomnia
  • headaches
  • abnormal heart rhythm

The effects of caffeine sensitivity are bothersome, but relatively minor. This isn’t the case for people who have a caffeine allergy. If you live with this allergy, consuming the smallest amount of caffeine can have a negative impact on your physical and mental health.

Physical symptoms of a caffeine allergy are similar to those caused by other food allergies. For example:

  • mouth, tongue, or lip itchiness
  • swollen lips or tongue
  • hives

These symptoms may begin shortly after consuming caffeine, or develop hours after exposure. Since caffeine allergies aren’t as well known, you may equate symptoms with another type of allergy.

A severe caffeine allergy can also produce anaphylaxis symptoms. Anaphylaxis symptoms include:

  • difficulty breathing because of swollen throat or tongue
  • wheezing
  • coughing

Symptoms of caffeine sensitivity are trigged by a sudden rush of adrenaline. People with a caffeine intolerance metabolize caffeine slowly.

A caffeine allergy develops when the immune system perceives caffeine as a harmful invader. The immune system produces the antibody immunoglobulin E. The antibody then travels to your cells, causing allergy symptoms.

Learn more: Allergic reactions »

Caffeine allergies are difficult to diagnose because they are so rare.

A skin test may be performed to diagnose a caffeine allergy. During your appointment, your doctor places trace amounts of the allergen on your arm, and then monitors your arm for a reaction. Developing redness, itchiness, or pain at the test site may confirm a caffeine allergy.

If you experience physical symptoms of a caffeine allergy, stop ingesting any food or drink that might contain caffeine and contact your doctor right away. Your doctor may advise you to take an over-the-counter antihistamine which may reduce symptoms such as itchiness, swelling, and hives. But the only way to prevent a caffeine allergy is avoiding foods and drinks containing caffeine.

It’s important to read food and drink labels.

Avoid Products With Caffeine

  • coffee (even decaffeinated coffee isn’t entirely caffeine-free)
  • tea
  • soft drinks
  • chocolate
  • frozen desserts
  • energy drinks
  • vitamin supplements
  • over-the-counter medications such as Excedrin Migraine

If you rely on caffeine for an energy boost, consider other ways to naturally boost your energy and stay alert. For example:

Increase physical activity

Start a workout routine and exercise for a minimum of 150 minutes each week. Jog, walk, ride a bike, or take a workout class.

Get plenty of sleep

Sleeping less than seven to nine hours a night can cause morning fatigue. Create a comfortable sleep environment and establish a regular bedtime routine. Turn off the TV and other electronic devices, and make sure your room is a comfortable temperature and dark.

Take vitamin supplements

Some vitamins can naturally boost energy levels over time. These include B vitamins, tyrosine, and rhodiola rosea. Talk to your doctor before starting a vitamin regiment, especially if you’re taking prescription medicine.

If you have a caffeine allergy and continue to ingest caffeine, your symptoms can worsen. And depending on the severity of a reaction, you may develop anaphylaxis symptoms, which can be life-threatening.

If you get a proper diagnosis and avoid caffeine, your symptoms should improve. Giving up caffeine can trigger withdrawal symptoms, such as headaches, fatigue, and shakiness. But these symptoms are short-term and typically resolve within a week.