An acute allergic reaction, also known as anaphylaxis, is a severe and potentially life-threatening allergic reaction that can occur within seconds or minutes of exposure to an allergen. It is characterized by a rapid onset and can lead to symptoms such as hives, itchy, pale, or flushed skin, low blood pressure, difficulty breathing, weak and fast pulse, nausea, vomiting, diarrhea, dizziness, and fainting. Anaphylaxis is caused by the immune systems overreaction to a harmless substance, leading to the release of a flood of chemicals that trigger the allergic symptoms. Common triggers of anaphylaxis include foods, insect stings, medications, and latex. Prompt treatment with epinephrine is crucial, and individuals at risk of anaphylaxis are advised to carry self-injectable epinephrine and seek immediate medical attention at the first sign of anaphylaxis, even if epinephrine has been administered. It is important to note that even if an individual has had only a mild anaphylactic reaction in the past, there is a risk of more severe anaphylaxis after another exposure to the allergen. Therefore, it is essential to be vigilant and prepared for potential future reactions.