Long Island's Best Allergist

The Allergy, Asthma, and Immunology team at Heart and Health Medical is led by renowned award-winning Allergist & Immunologist Dr. Luis Guida Jr. one of the most recognized medical authorities of Allergy & Immunology care in Long Island. Dr. Guida and The Allergy & Immunology team at Heart and Health Medical have 36 years of experience providing Allergy care for the Long Island Community in four locations; Massapequa, Coram, North Babylon, and Plainview.

  • 36 Years of Experience 

  • Accepts Most Health Insurances

  • Award-Winning & Recognized Medical Leader

  • Board Certified Allergist & Immunologist

  • Four Convenient Long Island Locations

  • Top-Rated Allergist & Immunologist In New York

Accepted Insurances


Board Certified in Allergy, Asthma and Immunology, Pediatrics

Dr. Louis E. Guida Jr. is a renowned Allergy & Immunologist with over 36 years of experience diagnosing, treating, and managing allergies, asthma, and immune disorders for members of the communities of Long Island, New York. Dr. Guida was initially awarded his medical degree from St. George’s University School of Medicine. He completed his internship and residency in Pediatrics at Monmouth Medical Center, Long Branch, New Jersey. He went on to complete two fellowships – Cystic Fibrosis (Adult and Pediatric) and Pediatric Pulmonology at Hahnemann University Hospital in Philadelphia, Pennsylvania, and Adult & Pediatric Allergy / Immunology at Nassau County Medical Center in East Meadow, New York.

Dr. Guida’s hospital affiliations are Good Samaritan Hospital Medical Center in West Islip, New York, and St. Charles Hospital, Port Jefferson, New York. He is an adjunct clinical assistant Professor of Pediatrics at the New York College of Osteopathic Medicine. He is the Medical Director of the adult and pediatric Cystic Fibrosis Programs and the Family Asthma and Allergy Center at Good Samaritan Hospital Medical Center. He is a fellow of the American Academy of Allergy, Asthma and Immunology, American College of Chest Physicians and the American Academy of Pediatrics.

Dr. Guida, Best Allergist in Long Island

Allergy Specialties

  • Adult & Pediatric Asthma
  • Allergy
  • Pulmonology 

Hospital Affiliations

  • Good Samaritan Hospital Medical Center
  • St. Charles Hospital

Fellowships & Memberships

  • Fellow of The American Academy of Allergy, Asthma, and Immunology
  • Fellow of The American Academy of Pediatrics
  • Fellow of The American College of Allergy, Asthma, and Immunology
  • Fellow of the American College of Chest Physicians
  • New York Allergy Society
  • Long Island Allergy Asthma Society
  • Cystic Fibrosis Foundation
  • American Medical Association

Patient Reviews

Nancy Kohlhoff
Nancy Kohlhoff
RoseAnn Larson
RoseAnn Larson
Melinda Lichioveri
Melinda Lichioveri
Mia Lembo
Mia Lembo
lori Friedmann
lori Friedmann
Dr.Guida has treated my daughter for asthma since she wes 2 1/2 years old, he is the best truly the best ! He bedside manner, his kind nature, and his approach to treating the asthma. I highly recommend him ! Thank you Dr. Guida !
Mark Businski
Mark Businski
Great service.
Louis Guida
Louis Guida
everili Sanchez
everili Sanchez
dr.guida best doctor I ever seen ..very happy ,show compassion,very profetional ... staff very friendly ...
Frank Keach
Frank Keach
Long Islands Best Allergist

Allergy Symptoms, Diagnosis, & Treatment

Understanding Allergies: How They Affect Your Immune System

Allergies are among the most prevalent chronic health conditions globally, ranging from mild discomfort to potentially life-threatening reactions. An allergy is essentially a misdirected response of the immune system, which normally protects us against harmful invaders such as viruses and bacteria.

In the case of an allergy, the immune system mistakenly identifies a typically harmless substance as a threat. This substance is known as an allergen. The immune system’s overreaction to this perceived invader involves the production of Immunoglobulin E (IgE) antibodies. These antibodies seek out and attach to certain cells, triggering them to release histamine and other chemicals. It’s this release of chemicals that leads to the various symptoms associated with an allergic reaction.

The complexity and intensity of allergy symptoms can vary widely, but understanding this basic mechanism is key to recognizing and effectively managing allergies.

The Three Primary Types of Allergens and Allergy Testing Explained

Allergies are triggered by various substances known as allergens, which can be classified into three primary types:

  1. Inhaled Allergens: These allergens enter the body through inhalation and affect the lungs or the membranes in the nostrils or throat. A common example is pollen, widely recognized as a major trigger of seasonal allergies.

  2. Ingested Allergens: These are allergens found in certain foods. Common ingested allergens include peanuts, soy, and seafood, which can cause allergic reactions in sensitive individuals.

  3. Contact Allergens: These allergens must directly touch the skin to cause a reaction. Contact with substances like poison ivy, for instance, can lead to a rash and itching.

To diagnose allergies, allergy tests are conducted. These tests typically involve exposing a small area of your skin to a very tiny amount of a specific allergen and observing the body’s reaction. This process helps in identifying which substances you are allergic to, enabling effective management of your allergies.

Allergy Testing

According to the American College of Allergy, Asthma, and Immunology, allergies impact over 50 million people in the USA, making them a significant health concern. Among various types of allergies, inhaled allergens are the most common. Seasonal allergies, also known as hay fever — an allergic response to pollen — affect more than 40 million Americans.

Allergy testing is a crucial step in identifying the specific allergens that trigger your reactions. These tests can pinpoint allergens ranging from pollens and molds to other environmental substances. Understanding your specific allergens can help in determining the right treatment approach, which may include medications or lifestyle changes to avoid triggers.

Typically, allergy tests involve exposing the skin to various allergens and observing the reaction. Common reactions include mild itching, redness, swelling, and the formation of small bumps known as wheals. These symptoms usually resolve within a few hours to days, and mild topical steroid creams can help alleviate discomfort.

While rare, it’s important to be aware that allergy tests can sometimes trigger a severe allergic reaction that requires immediate medical attention. This underscores the importance of conducting allergy tests under professional supervision in a controlled environment.

Types of Allergy Tests

  1. Blood Test

  2. Elimination diet

  3. Skin Test

    1. Patch Test

    2. Scratch Test

Long Islands Best Allergist

Allergy Shots

Allergen immunotherapy, commonly known as allergy shots, is an effective long-term treatment option for individuals suffering from allergic rhinitis, allergic asthma, conjunctivitis (eye allergy), or stinging insect allergies. This therapy is designed to decrease sensitivity to specific allergens, offering a path to significant and lasting relief from allergy symptoms.

The principle behind allergy shots is to gradually accustom the body to allergens, thereby reducing the immune system’s overreaction. Over time, this treatment can lead to a noticeable decrease in allergy symptoms and may also reduce the need for regular allergy medications.

One of the most compelling advantages of allergy shots is their potential to provide lasting symptom relief even after the treatment has concluded. This extended benefit makes allergen immunotherapy a cost-effective and appealing treatment option for many people seeking long-term management of their allergies.

Hospital Affiliations

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