The lack of respiratory effects of the ocular hypotensive drug latanoprost in patients with moderate-steroid treated asthma.

The use of beta blockers for glaucoma treatment may cause serious bronchoconstriction in patients with chronic obstructive pulmonary disease. The synthetic prostaglandin (PG) F2 alpha-analogue latanoprost (13,14,dihydro-17-phenyl-18,19,20-trinor-PGF-2-alpha-iso propylester) represents a new class of drugs for glaucoma treatment. In this study the pulmonary tolerability to latanoprost in 12 healthy volunteers and 11 (one withdrawal due to a sty before latanoprost treatment) subjects with moderate but stable steroid-treated intrinsic asthma was examined. Asthmatic subjects received 30 microliters of vehicle (placebo) at the scheduled administration times on baseline day. On a second day, a minimum of one week later, increasing concentrations (0.35, 115 and 350 micrograms/ml) of latanoprost were added to the vehicle and given topically to both eyes. Healthy volunteers were given latanoprost only. ECG, blood pressure, heart rate, forced expiratory volume (FEV1), peak expiratory outflow (PEF) and forced vital capacity (FVC) were recorded immediately prior to and 15, 30, 45 and 60 minutes after latanoprost. Asthmatic patients inhaled salbutamol (0.2 mg) at 60 minutes after the highest latanoprost dose. There were no significant differences in pulmonary function, blood pressure or heart rate after latanoprost in the healthy volunteers. Moreover, all parameters were unaffected in asthmatic patients on the day latanoprost was given compared to the baseline day. Latanoprost did not dampen the bronchodilator response to beta-2-adrenergic stimulation. It is concluded that latanoprost did not affect lung function in healthy subjects or in asthmatics after a total accumulated dose 10 times that clinically recommended for glaucoma treatment. Therefore, latanoprost appears to be safe for glaucoma treatment in patients with steroid-treated stable moderate intrinsic asthma.