Energy drinks and energy “shots” have become increasingly popular in recent years. Many people consume them with the belief that they will assist in endurance, concentration and stamina.

Last updated: 28 June 2017

People might not know that energy drinks, and particularly energy “shots”, can contain high levels of caffeine or ingredients containing caffeine such as guarana plant extract.

What is caffeine?

Caffeine is a drug which comes from the leaves, beans or nuts of different plants. It is a stimulant drug which means that it speeds up the brain and nervous system.

In addition to being present in energy drinks, caffeine is also found in coffee, chocolate, tea and some soft drinks. The caffeine content of drinks where it is found naturally (tea, coffee, chocolate) can also vary widely depending on how they are prepared.

Some prescription and over the counter medications may also contain caffeine, such as cough medicine, headache tablets and slimming products.

What are the effects of caffeine?

Caffeine can affect people in different ways and how it does depends on:

  • how much you consume
  • your height and weight
  • your general health
  • if you are pregnant or breastfeeding
  • your mood
  • whether you have caffeine often
  • whether you have caffeine on its own, with food or with other drugs (including alcohol).

Small amounts of caffeine may have the following effects:

  • you feel more awake
  • your heart beats faster
  • you urinate more
  • your body temperature rises
  • your digestive system produces more acid.

Excessive consumption can lead to caffeine toxicity which can cause:

  • heart palpitations
  • nausea
  • vomiting
  • headaches
  • becoming delirious (be confused, have hallucinations or be very excited)
  • insomnia
  • nervousness
  • pregnancy loss
  • dependence (and later withdrawal).

Large amounts of caffeine may make the problem worse for people who already have heart problems or anxiety disorders.

Keeping track of your caffeine intake

It is important to be aware of how many energy drinks or energy “shots” you have consumed, so that you can keep track of your overall caffeine intake.

How much caffeine is safe?

Your body's response to caffeine will depend on a number of factors including your weight and health. Although a safe level has not been determined yet, as a guide:

  • healthy adults of around 70kg weight should aim for no more than 400mg per day (about 4 cups of coffee)
  • pregnant and breast feeding women should have less than 200mg per day (about 2 cups of coffee)
  • children and young people should limit their intake of caffeinated drinks.

Energy drinks are required by law to indicate their caffeine content on the label, however the level can vary.

Food/Drink Average caffeine levels
250ml energy drink 77mg 1
500ml energy drink 158mg 1
375ml of typical cola drink 48.75mg 1
250ml instant coffee 60mg 1
250ml brewed coffee 80mg 1
1 short black/espresso coffee 107mg 1
250ml cup of tea 27mg 1
60g milk chocolate 10mg 1

1 NSW Food Authority

Mixing alcohol and energy drinks

Alcohol is a depressant drug that slows down the brain and nervous system. Mixing alcohol with any other drug can be risky. Mixing energy drinks with alcohol can place your body under stress.

As you drink more alcohol and become intoxicated, you may lose track of the number of energy drinks (and caffeine) you consume. This can increase the risk of caffeine toxicity.

How can I get help?

Contact your medical practitioner if you are worried about your caffeine intake or that of a friend or family member.

If you are worried about your alcohol consumption, contact the Alcohol and Drug Information Service (ADIS) on 1800 422 599 or (02) 9361 8000 or talk to your medical practitioner.

You should call triple zero (000) in an emergency.

More Information

More information on a wide range of other drugs and their affects as well as details on how to get help is available at NSW Health website Your Room​​

Current as at: Wednesday 28 June 2017