Anaphylaxis is a sudden and severe allergic reaction that occurs when the body’s immune system overreacts to a substance it incorrectly perceives as harmful — such as a vaccine component.

This reaction can develop quickly, often within 5 to 30 minutes, and can become life-threatening if not treated immediately.

In some cases, symptoms may last for several hours or even days.

Some people may have an allergic sensitivity to ingredients like gelatin, latex, or trace proteins in the vaccine.

If you or your child suffered a severe allergic reaction following vaccination, you may qualify for compensation through the VICP.

These cases are time-sensitive, so contact our firm right away to begin your claim and ensure your rights are protected.

Anaphylaxis after a vaccine comes on suddenly and intensely. Most people describe a sense that “something is very wrong” within minutes of receiving the shot.

The reaction can start with mild itching or flushing and quickly progress to full-body symptoms as the immune system releases large amounts of histamine and other chemicals into the bloodstream.

Common Early Symptoms

• Warmth or flushing of the skin

• Tingling or itching (especially on the face, hands, or scalp)

• Hives or red, raised welts that may spread quickly

• Feeling lightheaded or dizzy

• A sudden feeling of fear or anxiety

Progressive or Severe Symptoms

• Swelling of the lips, tongue, or throat, causing difficulty speaking or swallowing

• Tightness in the chest, coughing, or wheezing

• A racing or irregular heartbeat

• Nausea, vomiting, diarrhea, or stomach cramping

• Sudden drop in blood pressure leading to fainting or collapse

What It Feels Like in the Moment
People often describe it as feeling like their body is “shutting down” — with rapid heartbeat, weakness, and difficulty breathing happening all at once.

There’s often a sense of panic or confusion as oxygen levels drop and blood pressure plummets.

After the Reaction
Even after emergency treatment with epinephrine, individuals may feel shaky, exhausted, or disoriented for hours or days.

Anaphylaxis is a medical emergency. Immediate treatment with epinephrine (adrenaline) is essential to reverse the reaction and prevent death.

Emergency responders may also provide oxygen, intravenous fluids, or antihistamines.

People who have experienced anaphylaxis are often prescribed an epinephrine auto-injector (EpiPen) and advised to wear a medical alert bracelet.

• About 1 in 20 U.S. adults have experienced anaphylaxis at least once.

• Anaphylaxis occurs at a rate of 46 cases per 100,000 people per year worldwide, and the incidence is increasing by about 7.4% annually.

• 225 deaths per year in the U.S. are attributed to anaphylaxis.

• For Pfizer-BioNTech COVID-19 vaccine, the rate of anaphlaxis was 11.1 cases per million doses.

• For non-COVID vaccines, rates vary but are generally less than 1 case per 100,000 doses.