Title: Ethambutol related ocular complications of anti-tuberculosis drug therapy in Ibadan, Oyo state, Nigeria. Study design: The study is a multi-centre hospital-based prospective cohort study. Method: A sample size of 546 was used in the study. All eligible consecutive new patients presenting with pulmonary tuberculosis to the Jericho, Alafara, and Iwo road Ibadan were included in the study. Approval for the study was sought from Oyo state Research Ethical Review Committee Ministry of Health Secretariat Ibadan. Selected patients were examined before anti-TB medications were started. Eligible patients were recruited into the study. There were two groups in the study: the intervention group and the non-intervention group. Both groups received the anti-TB medications. Detailed ophthalmic examinations were done before the anti-TB drugs were started which included visual acuity assessment, anterior segment evaluation and colour vision test. After the initiation of treatment the patients were followed-up for a period of six months. They were examined at two weeks, one month, two months, four months and then six months after the treatment had been commenced. The last patients were followed up for six. The patients on the scheduled follow-up visits were examined for any sign of toxicity from Ethambutol anti tuberculosis medications. The patients in the intervention group were given a small cardboard paper that was painted red for self monitoring at their homes. The patients were taught how to use the red cardboard monocularly at their homes. They were instructed to report any perceived change in colour vision discrimination or visual acuity change and encouraged to seek ophthalmic evaluation as soon as possible. The patients in the non-intervention group were given the small cardboard paper that is painted white for view at their homes. Those patients that reported change in colour vision discrimination or visual acuity change were examined right away before their scheduled follow-up visit. The aforementioned ocular examinations were repeated on these patients. Data analysis: The data collected was entered and analyzed using statistical package for social sciences (SPSS) software version 21.