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Conjunctivitis - allergic - Evidence
Evidence on topical ocular antihistamines
Topical ocular antihistamines (e.g. azelastine, emedastine) are more effective than placebo. However, no evidence from randomized controlled trials supports the use of one type of topical ocular antihistamine over another:
- A systematic review and meta-analysis investigated the efficacy and effectiveness of topical treatments for seasonal allergic conjunctivitis. Topical ocular antihistamines were found to be superior to placebo, but there was insufficient evidence was insufficient to recommend the use of one type of antihistamine over another:
- The Cochrane Library, Embase, and Medline were searched up to 2001 for randomized controlled trials:
- Nine randomized controlled trials were identified, of which six (n = 271) compared treatment of levocabastine (no longer available in the UK) with placebo.
- A variety of symptoms and signs were graded using numerical symptom-severity scales or visual analogue scales.
- Formal meta-analysis was not possible because most studies did not tabulate the mean scores and error associated with these scores.
[Owen et al, 2004; Wormald et al, 2004]
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