Can allergic reactions trigger high blood pressure?

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Allergic reactions are considered as a scary ordeal by many, but for those who have high blood pressure, a miscalculated decision can be deadly. If the individual has issues with allergies and high blood pressure, a doctor should be consulted before attempting to use any over-the-counter treatment.

The individual is recommended to wear a medical alert bracelet for the conditions to ensure that proper treatment can be given if he/she loses consciousness from a severe allergic reaction.

Overview on blood pressure

The blood pressure is the amount of blood that pumps through the heart and degree of resistance to the flow in the arteries. In case the arteries are narrow, the heart has to strain to circulate the blood all over the body, thus the individual has high blood pressure. If the arteries are relaxed and dilated, the blood flows without resistance which leads to low blood pressure.

High blood pressure
The indications of dangerously high blood pressure include blurred vision, buzzing in the ears, severe headache, chest pain, anxiety, seizures as well as shortness of breath and heart palpitations.

When the blood pressure is checked, the reading has 2 numbers in which the first is the pressure in the arteries when the heart beats and the second is the pressure in the arteries between beats. The normal blood pressure level is below 120/80 mm Hg. If it is higher than 140/90 mm Hg, it is considered high blood pressure. Unless the allergic reactions are severe and life-threatening, the blood pressure is not likely to be affected.

Connection with allergic reactions

Allergic reactions occur once the immune system attempts to eliminate a substance that is relatively harmless. During the first exposure of the individual to the allergen, the body starts to produce antibodies that fight the substance on the next exposure.

On the next exposure with the allergen, the individual ends up with an allergic reaction. The reaction depends on the allergen and varies from one individual to another. Allergic rhinitis occurs when the allergen is inhaled which triggers issues with the throat, nose and ears. If it causes congestion at night time, difficulty breathing occurs that can lead to sleep apnea that can cause high blood pressure.

On the other hand, a systemic bodily reaction that occurs during anaphylaxis can reduce the blood pressure to dangerously low levels which results to an erratic heart beat and bluish skin due to the diminished level of oxygen. In severe cases, the individual goes into cardiac arrest.


Allergies that trigger stuffed nose are managed using decongestants but these medications can constrict the blood vessels which is dangerous for those who have existing high blood pressure.

Individuals who have high blood pressure must avoid using antihistamines unless directed otherwise by the doctor. During a severe allergic reaction, an individual should be given a shot of epinephrine which increases the blood pressure. The indications of dangerously high blood pressure include blurred vision, buzzing in the ears, severe headache, chest pain, anxiety, seizures as well as shortness of breath and heart palpitations.

Preventive measures

Allergic reactions can be prevented by avoidance of the allergen responsible for triggering the symptoms. It is sad to note that this is not always possible since the allergen is difficult to avoid or unidentified.

Once the doctor comes up with a personal plan in controlling the allergies that does not interfere with high blood pressure, it must be carefully followed. In addition, the individual should inform the doctor regarding any blood pressure medications used. The blood pressure increases steadily with age, but a significant increase can be prevented by minimizing the intake of salt in the diet, quit smoking, regular exercise, avoid heavy consumption of alcohol and minimizing the level of stress.

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