Toxic maculopathy. Part I. A result of quinine usage

A group of 16 heroin-dependent patients undergoing voluntary detoxification were studied to detect "toxic" quinine amblyopia." No true "amblyopia" was found but 8 of 16 (50%) patients had positive Amsler grid tests. This was called "toxic maculopathy." A control group of US Army reservists showed 1 of 25 (4%) to have positive Amsler chart tests. The difference between the two groups is significant and probably represents a chronic, low dose quinine macular toxicity. The strongly suggested relationship between chronic low doses of quinine and subtle macular changes led us to create a second study to document objective abnormalities. This study is presented in Part II.