Posters

The suppressive effect of topical β-adrenergic receptor antagonists on basophil activation in glaucoma patients

Poster Details

First Author: G.Shemesh ISRAEL

Co Author(s):    E. Rosenfeld   S. Kurtz   M. Lazar   S. Kivity     

Abstract Details

Purpose:

Brimonidine tartrate 0.15%, a highly selective topical α2 - adrenoreceptor agonist, is used for lowering intraocular pressure in glaucoma patients. The drug has an unexplained high rate of clinical hypersensitivity, which is reduced by approximately 50% with the addition of a β-blocker (Timolol). The basotest has proven to be valuable examination kit in diagnosing allergic drug reactions. We used the Basotest for the evaluation of hypersensitivity induced by brimonidine and the beneficial effect of adding timolol to it.

Setting:

Tel Aviv Medical Center, in Tel Aviv Israel

Methods:

Eight patients with a clinical hypersensitivity to Brimonidine and six healthy individuals as a control group were enrolled. Basotest was used to evaluate the percentage of basophile activation following exposure of blood samples to Brimonidine, Timolol and its combination. Eight patients with a clinical hypersensitivity to Brimonidine and six healthy individuals as a control group were enrolled. Basotest was used to evaluate the percentage of basophile activation following exposure of blood samples to Brimonidine, Timolol and its combination.

Results:

No basophil activation was observed in the studied patients exposed in vitro to brimonidine, however, there was a significant suppression of basoactivation when the combination drug was compared to timolol (P = 0.043) and to brimonidine (P = 0.068). This suppression was also seen when basophils from healthy control were tested.

Conclusions:

The data indicates that these drugs do not induce an allergic reaction. On the other hand basophil activation was suppressed by the presence of β-blockers in patients hypersensitive to brimonidine and in healthy individuals. This finding indicates that Timolol suppress brimonidine drug reaction by different mechanism. FINANCIAL INTEREST: NONE