Allergies and Sensitivities

Allergies and sensitivities to medications are different reactions that can occur when the body responds negatively to a drug.

A drug allergy occurs when your immune system mistakenly treats a medication as a harmful substance. In response, the immune system triggers an allergic reaction. This can range from mild to severe and, in some cases, can be life-threatening.

A drug sensitivity, on the other hand, isn’t caused by the immune system. Instead, it happens when a person reacts negatively to a medication because their body doesn’t metabolize it properly or reacts in an exaggerated way to a normal dose. This is more of a dose-dependent response, and symptoms are generally less severe than allergies but can still be uncomfortable.

Both allergies and sensitivities can vary in severity and may not appear immediately after taking a drug; some reactions may occur after a few days or longer. If someone suspects they’re having an allergic or sensitive reaction to a medication, it’s important to contact a healthcare professional right away. In some cases, an allergy can become more serious with repeated exposure, so identifying the offending drug and avoiding it in the future is key.

Allergies

Symptoms of Allergies

• Skin reactions: Rash, hives, or itching.
• Swelling: Swelling of the face, lips, tongue, or throat.
• Breathing problems: Wheezing, difficulty breathing, or tightness in the chest (anaphylaxis).
• Gastrointestinal symptoms: Nausea, vomiting, or diarrhea.
• Fever: Mild to moderate fever.
• Anaphylaxis: A severe, life-threatening allergic reaction that may cause difficulty breathing, a rapid drop in blood pressure, and even loss of consciousness.

Common Medicines that can Cause Allergies

• Antibiotics (like penicillin)
• Nonsteroidal anti-inflammatory drugs (NSAIDs) (like aspirin or ibuprofen)
• Certain vaccines
• Anticonvulsants (medications for seizures)

Sensitivities

Symptoms of Drug Sensitivities

• Nausea and vomiting
• Headaches or dizziness
• Drowsiness or fatigue
• Increased heart rate or palpitations
• Stomach pain or bloating
• Diarrhea or constipation

Common Medicines that can Cause Sensitivities

• Pain relievers like acetaminophen or ibuprofen
• Anti-inflammatory drugs
• Blood pressure medications
• Chemotherapy drugs