Dizziness or light-headedness is usually caused by a decrease in blood flow to the brain. This occurs in response to the slowing of the heart rate or a drop in blood pressure (hypotension). In extreme cases, this can lead to a sudden loss of consciousness, or fainting (syncope) . Hypotension and slowing of the heart rate as part of an allergic reaction to food are mediated by a chemical called histamine. Histamine has many effects on the body and is released by your immune system in response to a food allergen. It causes blood vessels to dilate or widen, thus resulting in a sudden and potentially severe drop in blood pressure .
Do Not Ignore This Symptoms
If you experience a feeling of dizziness or light-headedness after eating certain foods, you need to identify exactly what your triggers are, as this is classed as a moderate to severe reaction, and can often herald the onset of anaphylaxis. Anaphylaxis is the most severe allergic reaction, and can quickly become life-threatening. Immediate medical support should always be sought if the risk of anaphylaxis is high.
Track Your Triggers
If your symptoms are not severe but are still causing you discomfort and anxiety, a symptom and trigger tracking app like AlliApp can be extremely helpful. Often, when you have an allergy or intolerance to a food, your reactions worsen every time they occur. Therefore, it is extremely important that you identify your triggers. Keeping a record of what you are eating and any symptoms such as dizziness that occur even a few hours later is the most efficient way to do this. Some people can also experience blurred vision or confusion together with light-headedness, which also indicates a potentially severe allergic reaction to food.
Another important reason for using a symptom tracking app is that other underlying conditions could be responsible for any dizziness or light-headedness experienced. If food allergies or intolerances are not responsible for this, AlliApp can also help in eliminating foods as a cause of your symptoms, thus allowing you to explore other causes with your healthcare professionals.
Other articles of our series “The Six Main Symptoms of Food Allergy”:
- STARS (2018): Reflex Syncope (Neurally Mediated Syncope/Vasovagal Syncope) Available online at: http://www.heartrhythmalliance.org/stars/uk/reflex-syncope-vasovagal-syncope [Accessed 29/09/18]
- Encyclopaedia Britannica (2018) ‘Histamine Biochemistry’ Available online at: https://www.britannica.com/science/histamine [Accessed 01/10/18]