Ravimiallergia

Ravimiallergia, also known as drug allergy or medication allergy, is an adverse reaction of the immune system to a medication. It is not to be confused with drug intolerance, which is a side effect that does not involve the immune system, or drug toxicity, which is an overdose. Drug allergies can range in severity from mild rashes to life-threatening anaphylaxis.

The immune system mistakenly identifies a drug or its metabolite as a harmful substance and triggers an allergic response. This can involve the production of antibodies, such as IgE, which then cause the release of histamine and other chemicals that mediate allergic symptoms. Symptoms can appear within minutes of taking the drug, or they may be delayed, occurring hours, days, or even weeks later. Common symptoms include hives, itching, rash, swelling, wheezing, and difficulty breathing. In severe cases, anaphylaxis can occur, characterized by a sudden drop in blood pressure, rapid pulse, and difficulty breathing, requiring immediate medical attention.

Diagnosis of a drug allergy typically involves a thorough medical history, including detailed information about previous reactions to medications. Physical examination and specific allergy tests, such as skin tests or blood tests, may also be used, though their effectiveness varies depending on the specific drug.

The primary treatment for a drug allergy is to avoid the offending medication and any drugs that are chemically similar. For mild reactions, antihistamines or topical corticosteroids may be prescribed to manage symptoms. In cases of anaphylaxis, epinephrine is the first-line treatment, followed by other supportive measures. Desensitization, a process of gradually exposing the patient to small doses of the drug under medical supervision, may be an option for individuals who absolutely require a medication to which they are allergic.