In 1884, Viennese ophthalmologist Karl Koller discovered that a mild solution of cocaine applied to the eye would deaden the nerves' sensitivity to pain.
Notes on verification
Well-documented in medical history sources, encyclopedias, and peer-reviewed literature; consistent details across multiple independent references. [cascade flags: aggregator_dropped_primary_exists,wikipedia_dropped_other_sources_exist | tier=silver indep_score=0.925 clusters=2 claim_tier=notable | kind=empirical eligibility=high]
Sources
- Cocaine, the Victorian wonder drug | Wellcome Collection (seed:anatomy_and_medical_oddities)
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3140169/ (corroboration)
- https://www.aao.org/history-of-ophthalmology/karl-koller (corroboration)