Caffeine Poisoning: Can You Overdose on Caffeine?

Can You Overdose on Caffeine?

It is possible to overdose on caffeine. Caffeine overdose occurs when someone takes in more than a normal or recommended amount of caffeine in a certain period of time. Overdoses can happen by accident or on purpose. Fatal overdoses are rare and they depend on how much is consumed as well as your weight. It is important to seek immediate medical care if you are experiencing a caffeine overdose.¹

What is Caffeine poisoning?

Caffeine poisoning, also known as caffeine overdose or toxicity, is when an individual consumes an excessive amount of caffeine which can lead to serious side effects. It is diagnosed by symptom presentation and the timing of these symptoms in relation to any substances taken. Doctors will also rule out any other possible reasons for your symptoms since other conditions and substances can present with similar symptoms. Symptoms present in relation to stimulating the central nervous system, where an overdose can affect areas like your brain, heart, and GI tract.^{1, 2}

11 Caffeine Overdose Symptoms

The symptoms of a caffeine overdose results from the body becoming overstimulated due to caffeine being a stimulant. Overdoses can result in a serious change in mental status, such as confusion or a change in your state of alertness. Changes to the heart displays as an irregular or rapid heartbeat. Caffeine may also cause Below is a nonexhaustive list of symptoms that can be associated with a caffeine overdose.

Here are 11 number common caffeine overdose symptoms:^{1, 2}

1. Breathing trouble
2. Changes in alertness
3. Agitation, confusion, hallucinations
4. Seizures
5. Diarrhea
6. Dizziness
7. Fever
8. Irregular heartbeat
9. Muscle pain/breakdown
10. Nausea, vomiting
11. Changes in heart rhythm

Side Effects of Too Much Caffeine

Caffeine works as a stimulant in the body. When consumed, it can cause the body to become overactive and worsen certain conditions, like anxiety. Caffeine consumption may cause a person to experience GI issues, increased heart rate, and a general increase in energy that might make it hard to relax or sleep. If consumed frequently, a dependency or caffeine addiction may occur in which a sudden stop to ingesting caffeine may cause irritability and headaches.³

Side effects of too much caffeine include:

• Anxiety
• Heart palpitations
• Insomnia
• Dependency or caffeine addiction
• Tremors/jitters/twitches
• Restlessness
• Feeling of unhappiness
• Nausea
• Upset stomach
• Headache
• Increased urination

Causes of & Risk Factors for Caffeine Overdose

Caffeine overdoses occur when a person consumes too much caffeine in a given period of time. Some may have overdoses depending on present health conditions that may affect how they process caffeine in the body, such as liver and kidney impairments and pregnancy. Overconsumption of caffeine may also occur because people are unaware of how much caffeine they are actually consuming, such as if they are eating food or beverages that may contain more than they thought.

Common risk factors for caffeine overdose include:²

• Combining caffeine and alcohol: Alcohol is a depressant, and caffeine can mask the effects of alcohol in a person. Combining the two substances may cause a person to drink in excess.
• Women who are breastfeeding: Caffeine has the potential to pass through breast milk to infants. The CDC states that low to moderate intake of coffee should not affect the baby.
• Peptic ulcer disease or gastroesophageal reflux disease: Caffeine may make these conditions worse.
• Seizures: Caffeine may potentially lower the seizure threshold, meaning that someone who is predisposed to seizures.
• Those who regularly consume caffeine: The more a person consumes caffeine, the more likely it is that they have a tolerance to it. Building a tolerance to caffeine may lead a person to overconsume caffeine and overdose.
• Pregnancy: The American College of Obstetricians and Gynecologists (ACOG) considers 200 mg daily safe during pregnancy. Some studies may associate high caffeine consumption during pregnancy (over 400 mg daily) with low birth weights.
• Kidney/Liver impairment: These organs help to process medications and substances from the body. If these are impaired, then a person might have caffeine in the body for longer, increasing the risk of overdose.
• Severe anxiety: Caffeine can cause or worsen anxiety symptoms.
• Cardiovascular disease: Caffeine may increase blood pressure which may affect people with blood pressure issues and heart conditions. Caffeine may also cause irregular or fast heartbeats in excess.
• Overconsumption of products with caffeine: There is caffeine in many processed foods, and items like energy drinks can have a large amount of caffeine in them. Sometimes each can have a full day’s worth of caffeine, and some people might drink multiple cans thinking that they are within the limit.

Sources of Caffeine

Caffeine is found naturally in the leaves, seeds, and fruits of more than 60 plants, including tea leaves, kola nuts, coffee, and cocoa beans. It is also found in processed foods, added to beverages and supplements. Some beverages, like decaffeinated teas and coffee, still have small amounts of caffeine in them. There are medications that also have caffeine formulated into the medication, such as some over-the-counter migraine medications and decongestants.^{3, 4, 5}

Common Sources of Caffeine and Their Average Caffeine Content

Source of Caffeine	Average Caffeine Per Serving
Black Coffee	60-95 mg per 8 oz
Decaf coffee	2-15 mg per 8 oz
Espresso	65 mg per 1.5 oz
Black Tea	47 mg per 8 oz
Green tea	28 mg per 8 oz
Soda (cola)	40-55 mg per 12 oz
Chocolate	24 mg per1 oz
Caffeine tablets	200 mg per tablet
Energy drinks	85 per 8 oz
Energy shots	200 mg per 2 oz

Diagnosing Caffeine Overdose

A doctor may ask you what you have consumed if you are experiencing a caffeine overdose. Based on symptoms and the suspected amount of caffeine you have consumed, the course of treatment may vary. They will monitor you for other symptoms and will use an electrocardiogram (EKG) to monitor your heart’s rhythm and rate. Sometimes, your blood can be taken to analyze what your levels are to gauge if you need further supportive treatment. ⁶

At-Home Treatment for Caffeine Overdose Symptoms

Mild cases may be able to treat an overconsumption of caffeine at home. Symptoms like nervousness, jitteriness, and nausea can be managed at home. Home treatment may not always be the best choice, depending on the severity of your symptoms. If you are unsure whether you need treatment, call Poison Control at 800-222-1222 and describe your symptoms.

They will direct you on the best course of action and if you need further medical care. If your symptoms are severe (i.e., having breathing troubles, feeling faint or dizzy, having heart or chest problems, or changes in your mental state), then call 911 and seek immediate medical care. ⁶

In cases of mild caffeine overdose symptoms, a person can take the following steps for treatment at home:

• Not consuming any further caffeine
• Drinking water to rehydrate
• Take a walk and wait it out

When to Go to the Doctor for Caffeine Overdose

Those with mild symptoms may be able to treat themselves at home, but those who are experiencing serious side effects should seek immediate care as they need medical intervention. When talking with a doctor, inform them of the person’s age, weight, and condition; the name of the product they ingested; the time that it was swallowed; and the amount that was swallowed.

Those with serious symptoms may be treated with activated charcoal which binds to the caffeine that was ingested recently and can help reduce the amount circulating in your body. Hemodialysis, a process where the blood is cleaned and put back into the body, can be effective in severe, life-threatening cases of caffeine ingestion. Otherwise, the treatment is largely supportive, which involves hydration and checking that your blood pressure and heart rate are in acceptable ranges. The treatment you receive depends on when you consumed the caffeine, how much was consumed, and the severity of your symptoms.⁶

How to Prevent Caffeine Overdose

To prevent a caffeine overdose, avoid consuming excessive amounts of caffeine and be sure to follow limits recommended by the FDA. Some may be more sensitive to caffeine than others, and these individuals should consume less caffeine should that be the case. To prevent overdoses, be sure to carefully read labels on processed foods as some products, like energy drinks, may have multiple servings within a single container. Keeping track of how much caffeine you consume in a day can help to prevent any accidental overdoses.

How Much Caffeine is Too Much?

The U.S. Food and Drug Administration (FDA) considers 400 mg to be a safe amount of caffeine for a healthy adult to consume daily, while children under the age of 12 should not consume any food or beverages with caffeine. Adolescents 12 and older are recommended to have a caffeine intake limited to no more than 100 mg daily.³

Fatal doses of caffeine, while rare, have been reported to occur when approximately 1 gram (1000 mg) or greater is ingested, but that does not mean a person needs to take this amount of caffeine in order to experience a serious medical emergency.⁶

Outlook After Caffeine Overdose

Caffeine overdose can worsen preexisting health conditions, such as anxiety and heart problems. In severe cases, caffeine overdoses can result in acute kidney injury, the dangerous breakdown of muscles, and even result in cardiac arrest. The complications that arise from caffeine overdoses largely relate to how quickly the overdose is addressed and managed, so it is important to seek immediate medical care if you experience serious side effects.⁶

In My Experience

In my experience, caffeine overdoses rarely happen. Most people do not consume enough caffeine to experience serious symptoms, but overall I have noticed an increase in younger people consuming large amounts of caffeine. Drinks like energy drinks are often the culprit because they are easy to obtain and consume, and people who are unaware of how much caffeine is in a can may accidentally consume more caffeine than they are aware of. People should be aware of the recommended daily limits for caffeine and carefully read the labels on their foods and supplements to ensure they are not accidentally exceeding the limits.