Beta-adrenergic receptor blocking drugs: tear lysozyme and immunological screening for adverse reaction.

Patients who had received long-term therapy with practolol and other beta-adrenergic receptor blocking drugs were examined ophthalmologically. Tear lysozyme concentration and serum autoantibodies (antinuclear antibodies, DNA-binding antibodies and intercellular cement substance antibodies) were measured. It was found that beta-adrenergic receptor blocking drugs may have a pharmacological effect on the lachrymal glands, but this was not associated with dry eyes or adverse reaction. Practolol was found to be capable of reducing tear lysozyme concentrations to very low levels, and this was initially associated with high titres of ICC antibody. No other drug tested produced these effects.