|Year : 1982 | Volume
| Issue : 4 | Page : 253-256
Timolol for treatment of glaucoma
Ashok C Shroff
Gobind Mahal Mumbai, India
Ashok C Shroff
86-B, N. Subhash Road, Mumbai-402002
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Shroff AC. Timolol for treatment of glaucoma. Indian J Ophthalmol 1982;30:253-6
Timolol has been the most potent beta adrenergic blocking agent effectively lowering the intraocular pressure.
This survey was carried out at Shroff's Eye Clinic and at LTMM College, Sion.
| Material and methods|| |
The studies were based on the protocol devised by Merck Sharp & Dohme Research Laboratories, to assess the effect of Timolol in glaucoma and it's long term effects and it's side effects. A group of 75 cases were selected for a long term study which included cases of : 1. Ocular hypertension 2. Open angle glaucoma 3. Open angle glaucoma with central cataracts 4. Aphakic glaucoma.
The rest of the cases for short term investigations to assess the usefulness of the drug were 1. Acute congestive glaucoma 2. Subluxated lens 3. Congenital glaucoma 4. Open angle glaucoma treated with Timolol on first diagnosis 5. Normal eyes.
All the 70 cases except 5 cases of central cataract with glaucoma, in the long term study were already under treatment with either Pilocarpine of with miotics and Diamox, and were not controlled with treatment.
| Observations and discussion|| |
Ocular Hypertension and Open angle glaucoma
50 cases of ocular hypertension and open angle glaucoma were followed up with addition of Timolol 0.25 or 0.5% to the existing treatment.
1. In the first group of ocular hypertension, pressure was controlled with 0.25% and in open angle glaucoma, Timolol along with Pilocarpine, constituting 36% of cases. Average pressure from 22.8 mostly was maintained at 18.1 mmHg.
2. Those with higher tensions, not controlled with 0.25% were treated with 0.5% Timolol with existing treatment. 30% of the patients with this group of 50 patients were controlled resulting in 66%being controlled with drops. Remaining 34% were given Diamox also. 22%were still not controlled with treatment and were cases for surgery, besides none from those taking Diamox. This result showed, that 66% of patients were not controlled by Pilocarpine but were controlled by Timolol. The average tension was 30 mmHg'before treatment and 18.6mmHg after 3 months and 20 mmHg at 1 year.
Open Angle Glaucoma With Central Cataract
In 5 cases of open angle glaucoma with central cataract, patients had defective vision due to contraction of pupil with Pilocarpine, although the tensions were mostly controlled.
Replacing with Timolol helped to have normal pupil with less difficulty in reading and driving.
The group of aphakic glaucoma consisted of uncontrolled cases, which were not controlled with pilocarpine and some with Pilocarpine and Diamox. The tension was controlled only with Timolol in 10% of the cases. One patient used one drop every third day, totally 60% of the cases were controlled with drops and another 20% with addition of Diamox. The result in this group was remarkable as aphakic glaucoma has unfavourable prognosis even after surgery. The high average tension was due to uncontrolled cases which had very high tension. [Table - 1]
Acute Congestive Glaucoma
4 cases of acute congestive glaucoma were treated with Timolol, Pilocarpine, Diamox and Mannitol. As a large number of drugs were given in a short time followed by operation in a short period, it was not possible to assess it's effect, but it did not give any remarkable drop in pressure.
In one case of subluxated lenses the pressure dropped to 13 from 36 mmHg after adding Timolol to Pilocarpine and Diamox. On withdrawing Diamox it again went up to 59 mm Hg and remained high inspite of having Diamox.
In congenital glaucoma it had a small reduction from 40 to 33 mmHg. After trabeculectomy it reduced but was still 28 mmHg which was further controlled post-operatively by Timolol.
Open Angle Glaucoma
One drop of Timolol 0.5% was instilled on diagnosis in cases which were diagnosed as glaucoma for the first time and were not under any treatment.
Tension reduced from 37.2 mmHg to 11.5 mmHg (average) in 3 hours in the right eye and to 11.5 mmHg from 50 mmHg in 7 hours in the left eye.
One drop was instilled in normal eyes of cases. The tension dropped from 18 mmHg and 16 mmHg to about 11 mmHg in 3 hours and was minimum for 3 hours more after which it started rising. The fall was much less compared to a case of open angle glaucoma.
Co-efficient of Outflow
The outflow facility showed improvement over the year after treatment suggesting it's effect over it
Effect On BP and Pulse Rate
It has negligible effect on BP and pulse rate, and on pupil diameter was normal.
The adverse effects were fewer the commonest being heaviness of head with headache and dryness of eyes. Schirmer's test showed normal results in these cases.
Timolol is a distinctly superior drug for treatment of open angle glaucoma, aphakic glaucoma, glaucoma with central cataracts and has been a major achievement in treatment of glaucoma compared to Pilocarpine.
It is : (i) Long lasting (ii) More effective (iii) Sustained action for 12 hours (iv) Lesser side effects. No effect on pupil, vision and accommodation.
The only drawback is it's high cost. One bottle of Timmolol lasts for about 1 month.
[Table - 1], [Table - 2], [Table - 3], [Table - 4]