Can I be Allergic to Anesthesia?

When people express concerns about being “allergic to anesthesia,” they might be referring to different types of reactions. Some of these may be allergies, while others are side effects or non-allergic responses.

Types of Reactions to Anesthesia.

1. Allergic Reactions.

• IgE-Mediated Allergic Reactions – IgE anibodies are produced by the immune system causing the release of histamine. These are known as “classic allergies” and generally occur within minutes of being exposed to an allergen. IgE allergies can range from mild symptoms to an acute, severe reaction called anaphylaxis. Because they can become life threatenting, all allergy symptoms to anesthesic drugs should be taken seriously. Symptoms include:
  • Hives or Flushing.
  • Swelling.
  • Difficulty breathing.
  • Dizziness or fainting due to low blood pressure.
  • Rapid heart rate.
• Non-IgE-Mediated Allergic Reactions – Some allergic reactions don’t involve IgE antibodies but involve other parts of the immune system such as T-cells. Non-IgE allergies are very rarely life-threatening but can still cause troubling symptoms including:
  • Rashes.
  • Vomitting, diarrhea or stomach pain.
  • Fatigue.
  • Fever.
  • Joint pain.

Most Common Anesthesia Drug Allergies: Neuromuscular Blocking Agents & NSAIDS
Other Common Surgical Allergies: Latex, Antibiotics, and Contrast Dyes

2. Non-Allergic Reactions.

• Pseudoallergic Reactions – These reactions look like allergic symptoms (such as hives, flushing, or low blood pressure) but don’t involve antibodies or the immune system. They are due to the direct release of histamine or other substances from cells like mast cells. Pseudoallergies are fairly common and rarely severe.
• Side Effects – Nausea, vomiting, dizziness, sore throat (from intubation), muscle aches, and shivering are common side effects of anesthesia. These symptoms typically appear after waking up from surgery, unlike an acute allergic reaction, which usually happens immediately after exposure to a drug.

3. Other Adverse Reactions.

• Malignant Hyperthermia – A rare but serious reaction to some anesthetic drugs, causing a fast rise in body temperature and severe muscle contractions. This is not an allergic reaction but a genetic condition that requires quick treatment.
• Local Anesthetic Systemic Toxicity (LAST) – A rare but severe reaction that occurs when local anesthetics are absorbed into the bloodstream in high amounts, causing nervous system and heart problems.

Risk Factors for Allergic Reactions.

Several factors can increase the risk of an allergic reaction to anesthesia. These include:

• History of allergies.
• Personal or family history of reactions to anesthesia.
• Certain medical conditions like asthma, eczema, or mast cell disorders.

Preventing and Managing Allergic Reactions.

Before surgery, it is crucial for patients to share their full medical history with the healthcare team. This includes any known drug allergies or previous reactions to anesthesia. The doctor may recommend pre-operative tests, such as skin tests, to identify allergens in anesthetics.

If an allergy is detected, the anesthesia provider can select different drugs and may adjust the anesthesia plan to minimize the risk of a reaction. During surgery, the medical team will closely monitor the patient’s vital signs for any adverse reactions.

Other Common Questions about Anesthesia Allergies.

Can I Have an Allergy to Anesthesia Hours or Days After Surgery?

Although less common, patients may experience an allergic reaction to anesthesia hours or even days after surgery. These delayed allergies, known as non-IgE-mediated allergic reactions, involve other parts of the immune system, such as T-cells, rather than IgE antibodies. This causes symptoms to develop more slowly.

Patients may experience symptoms such as skin rashes, fever, joint pain, or swelling, which could indicate a delayed allergic reaction. However, these symptoms might also be due to lingering 1) side effects from anesthesia and surgery or 2) pseudoallergic reactions to new medications or dietary changes. Although these non-IgE reactions are typically not severe, they can still cause distress and should be reported to a healthcare provider.

Can I Have an Allergy to Dental Anesthetics?

Like with all anesthetics, allergies from dental anesthetics are rare. Dental anesthesia mainly uses local anesthetic drugs. Allergic reactions, when they do occur, are often from components like preservatives in the anesthetic. Sulfites are commonly used to preserve epinephrine, a common additive drug used in local anesthetics.

Patients may also have expected side effects from the local anesthetic itself. These are usually mild and include pain, redness, or swelling. In rare cases, patients may experience local anesthetic systemic toxicity (LAST). This is a serious complication that can result in dizziness, confusion, loss of consciousness, irregular heartbeat and large changes in blood pressure.