An in-service investigation of the additive effect of topical adrenergic agonists and beta-blockers.
BACKGROUND
We assessed the long-term additive effect of topical adrenaline or adrenaline precursor and beta-blockers because of doubts as to the presence and persistence of such an effect.


METHODS
In 43 patents (20 males and 23 females; mean (+/- SD) age 68.4+/-11.5 years, range 24-84 years) on combined therapy for a mean 4.6+/-4.4 years (range 3 months to 17 years) for chronic open-angle glaucoma, the adrenaline or adrenaline precursor drop was stopped for 4 weeks in both eyes of 27 patients and in one eye of 6 patients.


RESULTS
There was a mean rise in intra-ocular pressure (IOP) for the whole group from 17.5+/-4.0 to 18.7+/-4.9 mmHg (range 10-28 and 9-31 mmHg, respectively) on stopping adrenergic agonist drops. Three different responses were identified: (i) a rise in IOP > 2 mmHg (mean 5.8+/-3.2 mmHg; range 3-14 mmHg) in 20 eyes of 15 patients; (ii) no rise or fall > 2 mmHg in 43 eyes of 23 patients, with a mean rise of 0.2+/-1.1 mmHg; and (iii) a fall in IOP of > 2 mmHg (mean 5.6+/-3.2 mmHg; range 3-11 mmHg) in seven eyes of five patients.


CONCLUSIONS
The effect of adrenergic agonist and beta-blocker drops is variable, but an additive effect may be strong and persistent n some eyes, suggesting considerable variation in the distribution and density of adrenoceptors in different eyes. Therefore, there may be some variation in the effect of new alpha2-adrenoceptor agonists, but such effects should be additive to those of beta-blockers.
The Royal Victorian Eye and Ear Hospital, East Melbourne, Australia.
W E
WE
Gillies
A M
AM
Brooks
D000287:Administration, Topical; D000322:Adrenergic Agonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015784:Betaxolol / Q000008:administration & dosage / Q000627:therapeutic use; D002908:Chronic Disease; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D004837:Epinephrine / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000627:therapeutic use; D005260:Female; D005902:Glaucoma, Open-Angle / Q000188:drug therapy*; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions; D013999:Timolol / Q000008:administration & dosage / Q000627:therapeutic use; D014065:Tonometry, Ocular
D000322:Adrenergic Agonists; D000319:Adrenergic beta-Antagonists; D009883:Ophthalmic Solutions; D013999:Timolol; C015173:dipivefrin; D015784:Betaxolol; D004837:Epinephrine