What are the recommended antihistamines (anti-histamine medications) for treating allergies?

Recommended Antihistamines for Treating Allergies

Second-generation antihistamines are strongly recommended over first-generation antihistamines for treating allergic conditions due to their improved safety profile and reduced sedative effects. 1

Types of Antihistamines

First-Generation Antihistamines

• Associated with significant sedation, performance impairment, and anticholinergic effects (dry mouth, urinary retention) 1, 2
• Examples include diphenhydramine, chlorpheniramine, and brompheniramine 1, 3
• Should be avoided in children under 6 years due to safety concerns 1, 3
• Can cause performance impairment even when patients don't feel drowsy 1
• Primarily used in acute allergic reactions as adjunctive therapy to epinephrine 4

Second-Generation Antihistamines

• Preferred for allergic rhinitis and chronic allergic conditions due to minimal or no sedation 1, 2
• Examples include cetirizine, desloratadine, fexofenadine, levocetirizine, and loratadine 1, 5
• Well-tolerated with good safety profiles in children 1
• More effective when used continuously rather than intermittently for seasonal or perennial allergic rhinitis 1

Comparison of Second-Generation Antihistamines

• Fexofenadine: Truly non-sedating even at higher than FDA-approved doses 1, 6
• Loratadine and desloratadine: Non-sedating at recommended doses but may cause sedation at higher doses 1, 7
• Cetirizine: May cause mild sedation (13.7% compared to 6.3% with placebo) at standard doses 1, 6
• Intranasal azelastine: May cause sedation at recommended doses 1

Recommendations by Patient Population

Adults

• Fexofenadine is recommended as first-line therapy due to its non-sedating properties even at higher doses 1, 8
• Loratadine or desloratadine are good alternatives if fexofenadine is not available 1, 7
• Cetirizine may be considered if higher potency is needed, despite potential mild sedation 1, 6

Children

• Second-generation antihistamines are preferred for children 1, 8
• Fexofenadine is recommended as first choice due to its favorable safety profile 8
• Avoid first-generation antihistamines in children under 6 years 1, 3

Older Adults

• Second-generation antihistamines are strongly preferred due to increased sensitivity to sedation and anticholinergic effects 1, 8
• Fexofenadine is particularly advantageous due to its non-sedating properties 1
• First-generation antihistamines should be avoided due to increased risk of falls, fractures, and cognitive impairment 1

Effectiveness for Specific Symptoms

• Oral antihistamines effectively reduce rhinorrhea, sneezing, and itching associated with allergic rhinitis 1
• Limited effect on nasal congestion in allergic rhinitis 1
• H1 antihistamines are useful for relieving itching and urticaria but do not relieve respiratory symptoms in anaphylaxis 4

Important Considerations and Precautions

• Intranasal corticosteroids are more effective than antihistamines for controlling the full spectrum of allergic rhinitis symptoms 1
• In anaphylaxis, antihistamines should be considered adjunctive therapy and should not be substituted for epinephrine 4
• For allergic rhinitis with itching symptoms, second-generation antihistamines like fexofenadine are generally preferred 8, 9
• Be cautious with standard doses of loratadine or desloratadine in patients with low body mass, as they may experience sedation due to higher relative dosing 1, 8

Common Pitfalls to Avoid

• Don't assume all second-generation antihistamines have the same sedation profile; there are important differences 1, 8
• Avoid first-generation antihistamines for routine management of allergic conditions due to significant sedation and cognitive impairment 1, 2
• Don't substitute antihistamines for epinephrine in the treatment of anaphylaxis 4
• Continuous treatment is more effective than intermittent use for seasonal or perennial allergic rhinitis 1