Anaphylaxis is a life-threatening allergic reaction that can be caused by exposure to certain allergens.

  • What is it
  • Symptoms
  • Treatment
  • Prevention


What is it

Anaphylaxis is a life-threatening allergic reaction that can be caused by exposure to certain allergens. The immune system becomes sensitized to a particular allergen (sensitizing dose), and later exposure to the offending allergen causes a severe, whole body allergic reaction. Anaphylaxis is triggered when the immune system overreacts to a usually harmless substance (an allergen such as peanut or antibiotic like penicillin) causing mild to severe symptoms that affect various parts of the body. Symptoms usually appear within minutes to a few hours after eating a food, swallowing medication or being stung by an insect. Sometimes symptoms go away, and then return a few hours later, so it is important to get to a hospital (call 911) or seek medical care as soon as an anaphylactic reaction begins and to remain under medical observation for as long as the reaction and symptoms continue.



Symptoms normally occur within seconds to minutes, but can occur hours later after the exposure to the allergen. They include the following:

  • Abdominal pain or cramping
  • Abnormal (high-pitched) breathing sounds
  • Anxiety (impending sense of doom)
  • Chest pain/tightness
  • Confusion
  • Cough
  • Cramping of the uterus
  • Diarrhea
  • Difficulty breathing
  • Difficulty swallowing
  • Fainting, light-headedness, dizziness
  • Headache
  • Hives, itchiness
  • Hoarse voice
  • Itchy mouth/throat
  • Itchy/red/watery eyes
  • Low blood pressure
  • Nasal congestion /stuffiness
  • Nausea, vomiting
  • Pale/blue color
  • Rash
  • Sensation of feeling the heart beat (palpitations)
  • Shock
  • Shortness of breath
  • Skin redness
  • Slurred speech
  • Swelling
  • Wheezing



Anaphylaxis is a life-threatening emergency condition requiring immediate medical attention. Patients with known severe allergic reactions may carry an EpiPen or other allergy medications and should be aided, if needed.  If anaphylaxis occurs or the patient needs to use an EpiPen, the patient should seek medical care immediately.



The patient should try to avoid known allergens and should be monitored if experiencing an allergic reaction. On occasion, after being pretreated with corticosteroids and antihistamines, patients who have a history of drug allergies may safely be given the medication causing the allergic reaction.

Indoor Allergies
Eye Allergies
Food Allergies
Children’s Allergies
Drug Allergies
Outdoor Allergies
Skin Allergies
General Allergies

“My son has been going to Dr. Mery for over a year.  I always appreciate how attentive the nurses are to him when checking him out before he is released after his shot.  This office is very clean and organized as well.”

Stephanie H.

“My whole family goes to Dr. Mery.  He has been a major factor in our family’s health and well-being.  Dr. Mery is compassionate and understanding.  He is determined to help those who come to see him and truly cares for his patients.”

Susan D.

“Hill Country Allergy has been a very good experience for me these last few weeks. A great team has been providing me with a thorough job of evaluating my allergy needs and implementing a specific plan to reach my specific goal of setting my allergies under control. All staff is efficient, courteous, and very knowledgeable of my specific concerns. I am very pleased with my current service.”

Sandra B.

“The staff at Hill Country Allergy & Asthma is nothing short of amazing. They greet you with a smile and they actually remember my name; you are not just another face. They are patient and take the time to explain things even if you ask them the same questions every other time you are there. The technicians providing the shots are extremely careful and service is usually quick due to the check in system they utilize. They are well organized, with excellent customer service.”

Ditrell B.

“Whenever Julie is the one who gives me my shot, I almost look forward to getting the shot. Her sunny disposition brightens my day. I did say that it almost makes me want to get a shot!”

Bob B.

“I have been very pleased with the great care I have received from Dr. Mery, as well as his entire staff. They are all great!”

Cindy M.

“I look forward to getting my allergy shots every month. The office staff is so friendly and professional. It is a very nice and relaxed atmosphere too.”

Maria B.

“Dr. Mery saved me! I struggled for months with a skin reaction that three other doctors were unable to get under control.  It was clear from the onset that Dr. Mery is truly invested in his patients as he spent so much time with me trying to understand my situation and helped me tremendously with my condition.  Dr. Mery and his staff genuinely care for their patients!”

Krista H.

“My son saw Dr. Mery years ago for his bad allergies.  He was tested, started shots and has been on shots for a couple of years now.  We cannot begin to express our gratitude to HCAA for helping our family.  Our son is completely different kid – he can now play on sports teams and enjoy playing outside with his buddies!  THANK YOU DR. MERY!”

Sandy H.