ORAL ANTIHISTAMINES
Place in Therapy
Place in therapy
Oral antihistamines should be used with topical agents in SAC. First generation oral antihistamines may cause extensive central nervous system and gastroinstestinal side effects. Second generation antihistamines are developed to reduce these side effects. Second generation antihistamines significantly dampen or block the early-phase and some of the features of the late phase response including swelling and redness1.
Comparatively, second generation oral antihistamines are not as effective as topically applied agents in treating allergic conjunctivitis and can cause drying of mucous membranes such as conjunctiva, which may exacerbate symptoms and counter the washing action of the tears from removing allergens from the ocular surface. However, several studies have shown improved efficacy when they are combined with topical anti-allergic agents2.
References
1. Bielory L, Lien KW., Bigelsen S. Efficacy and Tolerability of Newer Antihistamines in the Treatment of Allergic Conjunctivitis. Drugs 2005: 65 (2): 215-218.
2. Bilkhu PS, Wolffsohn JS, Naroo SA. Review of non-pharmacological and pharmacological management of seasonal and perennial allergic conjunctivitis. Contact Lens & Anterior Eye 35 (2012) 9-16.
Oral antihistamines should be used with topical agents in SAC. First generation oral antihistamines may cause extensive central nervous system and gastroinstestinal side effects. Second generation antihistamines are developed to reduce these side effects. Second generation antihistamines significantly dampen or block the early-phase and some of the features of the late phase response including swelling and redness1.
Comparatively, second generation oral antihistamines are not as effective as topically applied agents in treating allergic conjunctivitis and can cause drying of mucous membranes such as conjunctiva, which may exacerbate symptoms and counter the washing action of the tears from removing allergens from the ocular surface. However, several studies have shown improved efficacy when they are combined with topical anti-allergic agents2.
References
1. Bielory L, Lien KW., Bigelsen S. Efficacy and Tolerability of Newer Antihistamines in the Treatment of Allergic Conjunctivitis. Drugs 2005: 65 (2): 215-218.
2. Bilkhu PS, Wolffsohn JS, Naroo SA. Review of non-pharmacological and pharmacological management of seasonal and perennial allergic conjunctivitis. Contact Lens & Anterior Eye 35 (2012) 9-16.