Allergy (drugs)

Question 1

H1 Antihistamines

Answer 1

Inverse agonists at H1 histamine receptor
Best used before exposure to allergen
1st generation eg chlorpheniramine
Considerable sedation, drug interactions
2nd generation eg cerizine, loratidine, desloratidine, fexofenadine
No/ minimal sedation, once-daily

Question 2

Leukotriene receptor antagonists

Answer 2

• Only UK drug is montelukast
• Reduces early allergic responses, but inferior to H1 antihistamines

Used in chronic asthma

Question 3

Steroids

Answer 3

• Immunosuppression
• altering gene expression in numerous cell types, including T cells, B cells and cells of the innate immune system.
• onset of action is delayed and they must be taken regularly

Question 4

Omalizumab

Answer 4

Monoclonal antibody directed against IgE, used for atopic asthma (amongst other things)

Question 5

Allergen-specific immunotherapy

Answer 5

Allergen doses administered by subcutaneous injection or sublingually
Provide long-term protection
Mainly venom allergy and rhinitis

Effects- reduces allergen specific IgE levels, reduces mast cell responsiveness