Timolol Maleate V/s Timolol Maleate with Brimonidine in the Management of Open-Angle Glaucoma Patients with Moderate Intraocular Pressure

Abstract

Aim: Comparative study between timolol maleate and timolol – brimonidine combination in
treatment of open-angle glaucoma of moderate intraocular pressure in a tertiary care hospital
Methods: This observational comparative was carried out in the Department of Pharmacology,
Darbhanga Medical College and Hospital, Laheriasarai, Darbhanga, Bihar, India. The total
number of cases comprises of 100, with 50 in each group. In some patients both their eyes were
involved hence I.O.P was measured separately. The concentration of the monotherapy was
0.5% w/v Timolol Maleate. The concentration of the combination therapy was 0.2% w/v
Brimonidine Tartrate and 0.5% w/v Timolol Maleate. Both drugs were instilled in the affected
eye, twice daily (once in morning and once at night), for a period of four weeks.
Results: There was not much of a significant difference in the gender of the patients, both
males and females were affected equally in case of the combination therapy, and the
preponderance of female patients (56%) was seen in case of monotherapy of timolol. There
was no direct correlation to the presence of comorbidities in the patients. Around 42% was
present with both DM (Type 1) and Hypertension in case of monotherapy of timolol. In the
case of Timolol-Brimonidine combination, 54% of the patients presented with DM (type 1)
and 52% of the patients with Hypertension. This slight increase may be due to the increase in
the age of the patients undergoing combination therapy when compared to monotherapy. While
40% of the patients in both the groups had POAG in both their eyes, the remaining patients
developed POAG in either the right eye or the left eye. The other eye was only suspected to
have glaucoma and the IOP was less than 20mmHg. Hence the sample size to test the efficacy
of the drug therapy is a total of 140 eyes, with 70 under each group. Monotherapy of Timolol
is seen to lower the IOP at 26% in 3 days, whereas the Timolol-Brimonidine combination
therapy lowers the IOP at twice the rate that is 42.86% in 3 days. After reaching a I.O.P of
12mmHg, which is the normal IOP, both the drugs are used for maintenance therapy.
Conclusion: Timolol monotherapy provides the same result as the Timolol-Brimonidine
combination therapy and is also comparatively cheaper. Therefore, Timolol monotherapy is
better suited for the treatment of POAG in a tertiary care hospital.