Did You Know?
About 1.4 billion cups of coffee are consumed daily all over the world, with the highest consumption being in Europe.
Most of us start our day with a cup of tea or coffee, which are both sources of caffeine. Caffeine is a xanthine alkaloid that is found in cocoa beans, coffee beans, tea leaves, yerba mate, and guarana. It binds to adenosine receptors in the brain, which in turn prevents the natural sedative adenosine from attaching itself to the receptors. This drives away sleep and promotes wakefulness. It is a very effective nervous system stimulant; its absorption takes place at a very fast rate, and its effect can be felt in minutes. Some of the other common sources of caffeine include soda pops, energy drinks/bars, colas, and chocolate. Certain drugs or supplements also contain caffeine.

Caffeine is well tolerated, when used in moderation. However, excessive intake of this alkaloid in any form must be curtailed, as adverse effects are associated with an overdose. Moreover, some people might be more sensitive to caffeine than others or intolerant to caffeine. In case of individuals who are caffeine-intolerant, their body might not be able to metabolize or tolerate certain substances in this alkaloid. This gives rise to untoward symptoms. However, in case of individuals who are allergic to caffeine, the immune system might respond by causing symptoms that could even be life-threatening. Though there is less documentation about allergic reactions to caffeine, as caffeine allergy is not very common, medical help must be sought by anyone who develops an allergic reaction after ingesting caffeine-rich food.

Difference Between Caffeine Allergy and Caffeine Intolerance

Many people confuse food intolerance with a food allergy. Often, any adverse reaction that is experienced after the ingestion of a food is mistaken to be a food allergy. However, it must be noted that a true food allergy is said to occur, only due to a hypersensitivity reaction, wherein the immune system mistakes a substance to be a threat, thereby triggering a series of reactions. An allergy is categorized into immediate (IgE mediated) and delayed (mixed IgE/non-IgE and non IGE mediated). In case of an IgE mediated allergy, the allergic reaction is caused by the IgE allergy antibodies, with the symptoms ranging from urticaria (hives) to severe reactions such as anaphylaxis. A skin prick test or radioallergosorbent test can be used to identify the IgE antibodies. In case of delayed allergy, the symptoms include skin problems or gastrointestinal symptoms, and could be due to an immunological response mediated by IgG antibodies.


It must be noted that the symptoms of food intolerance could be quite similar to a delayed food allergy/allergy mediated by non-IgE antibodies. Thus, it can sometimes be difficult to assess whether one has developed a delayed food allergy or food intolerance. However, a true allergy is easier to identify, as there is a rapid onset of symptoms after the ingestion of food.

The common symptoms associated with a true allergy include:

Runny nose
Itchy/scratchy throat
Difficulty in breathing
Swelling of the throat/tongue/lips/face
Difficulty in swallowing
Heart palpitations
Nausea and/or vomiting
Abdominal cramps

It must be noted that sometimes adverse effects associated with caffeine intake could be due to a caffeine overdose or toxicity. Caffeine stimulates the adrenal glands to produce stress hormones such as cortisol and adrenaline, which in turn induces alertness. At times, people who are more sensitive to caffeine than others might experience the fight-or-flight response, which can cause symptoms such as:

Rapid heartbeat
Fast pulse
Increased rate of breathing
Muscle tension

Treatment and Precautionary Measures

While the symptoms caused by intolerance to caffeine might be discomforting, they might not be as serious as anaphylaxis that might occur if one is allergic. However, it is still advisable to take precautionary measures to avoid the symptoms related to caffeine intolerance. In case of an allergy as well as intolerance, the avoidance of the food is the best treatment option. It is also essential to identify the food items that contain caffeine. At times, the symptoms that might occur after the ingestion of coffee, tea, or other common food items that contain caffeine might not even be linked to caffeine. It's possible that the reaction is caused by some other ingredient used in that food item. Getting a skin prick test or following an elimination diet can help the doctors ascertain the allergenic food or the food that the patient might be intolerant to.

If you often experience symptoms after having caffeinated drinks or food, it would be best to read the food labels carefully so that you know which food items contain caffeine. In case of an allergy or intolerance, it would be best to avoid taking caffeinated drinks and food. Also, get some tests done to rule out lactose intolerance, and find out if you have any other type of food allergy or intolerance. Before you start following an elimination diet, do consult a doctor or a registered dietitian/nutritionist.

Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.