Allergic Reaction

2 medicines

An allergic reaction happens when the immune system overreacts to a harmless substance such as pollen, food, or a medicine, causing symptoms from mild itching and hives to severe swelling. Antihistamines and corticosteroids are the main treatments.

Orapred

Prednisolone

2.5/5/10/20/40mg

Orapred is a painkillers medication containing Prednisolone, available as 2.5/5/10/20/40mg tablets.

from $0.35 / tablet View

Prelone

Prednisolone

5/10/20/40mg

Prelone is a painkillers medication containing Prednisolone, available as 5/10/20/40mg tablets.

from $0.32 / tablet View

Key facts

  • An allergic reaction happens when the immune system responds to something it mistakenly flags as a threat: pollen, food, insect stings, latex, or a medicine.
  • Mild reactions cause itching, hives, sneezing, watery eyes, or a runny nose; severe reactions (anaphylaxis) can cause breathing difficulty, a sudden drop in blood pressure, or loss of consciousness.
  • Antihistamines settle mild symptoms quickly; more significant inflammation may need a short course of a corticosteroid such as prednisolone.
  • Anaphylaxis is a medical emergency: go to the nearest emergency department immediately.

What an allergic reaction looks and feels like

Mild-to-moderate reactions typically involve itching, hives (raised, red welts on the skin), sneezing, watery eyes, or a runny nose. Reactions to food or insect venom can also cause swelling of the lips, tongue, or throat. In humid climates, exposure to triggers can be constant rather than seasonal, making allergic reactions a common reason people seek care. More severe reactions, known as anaphylaxis, come on quickly and may include difficulty breathing, a sudden drop in blood pressure, or loss of consciousness. Anaphylaxis is a medical emergency: go to the nearest emergency department immediately.

How allergic reactions are treated

For mild reactions, antihistamines settle itching and hives quickly. When inflammation is more significant, a widespread rash, facial swelling, or persistent symptoms, a short course of a corticosteroid such as prednisolone helps calm the immune response. Severe or recurrent reactions sometimes need a broader pain management plan if the reaction causes significant discomfort.

When to see a doctor

Seek emergency care immediately for any sign of anaphylaxis. For milder reactions that keep recurring or don't settle with an antihistamine, see a doctor to identify the trigger and plan ahead, including whether an emergency adrenaline device is needed.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.