Therapeutic role of triple drug regimen of pentoxifylline, cilostazol, and methylcobalamin for visual recovery in ethambutol induced neuropathy

Main Article Content

Dr. Perwez Khan Dr. Shweta Singh Dr. Alok Ranjan Dr. Lubna Khan Dr. Indu Yadav

Abstract

Purpose: To evaluate the efficacy of a novel oral combination therapy—pentoxifylline, cilostazol, and methylcobalamin—in improving visual and electrophysiological outcomes in patients with ethambutol-induced optic neuropathy (EON).


Methods: A prospective interventional study was conducted on 34 patients (68 eyes) diagnosed with EON. Patients were randomly divided into two groups. The intervention group (n = 17) received oral pentoxifylline (16–18 mg/kg/day in two divided doses), cilostazol (50 mg/day), and methylcobalamin (1500 mcg/day) for 6 months. The control group (n = 17) received methylcobalamin alone for the same duration. Patients were evaluated at baseline and followed up at 1.5 months intervals for 6 months. Assessments included best-corrected visual acuity (BCVA) using early treatment diabetes retinopathy study (ETDRS) chart, contrast sensitivity via Pelli-Robson chart, color vision using Ishihara plates and fundus examination. Visual evoked potentials (VEP) with reverse pattern stimulation were performed at baseline and 6 months.


Results: The intervention group demonstrated significantly greater improvement in BCVA (mean gain: 0.71 ± 0.21; p = 0.001) and contrast sensitivity (0.697 ± 0.02; p = 0.002) compared to controls. VEP revealed a significant reduction in P100 latency in the intervention group (4.18 ± 1.23 ms; p = 0.003), indicating better optic nerve recovery, whereas latency worsened in the control group. Color vision improvement was not statistically significant (p > 0.05) in both groups.


Conclusion: The combination of pentoxifylline, cilostazol, and methylcobalamin significantly improved visual and electrophysiological parameters in EON patients. This multi-targeted neuro-regenerative therapy may represent a promising adjunct in the management of drug-induced optic neuropathies.

Keywords: Ethambutol-induced optic neuropathy, Pentoxifylline, Cilostazol, Methylcobalamin, Visual Evoked Potential, Best-Corrected Visual Acuity

Article Details

How to Cite
KHAN, Dr. Perwez et al. Therapeutic role of triple drug regimen of pentoxifylline, cilostazol, and methylcobalamin for visual recovery in ethambutol induced neuropathy. Medical Research Archives, [S.l.], v. 13, n. 5, may 2025. ISSN 2375-1924. Available at: <https://esmed.org/MRA/mra/article/view/6588>. Date accessed: 21 june 2025. doi: https://doi.org/10.18103/mra.v13i5.6588.
Section
Research Articles

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