The first documented case of LQTS was described in Leipzig by Meissner in 1856, when a deaf girl died after her teacher yelled at her. When the parents were notified of her death, they reported that her older brother, who also was deaf, died after a terrible fright.  This was several decades before the ECG was invented, but is likely the first described case of Jervell and Lange-Nielsen syndrome. In 1957, the first case documented by ECG was described by Anton Jervell and Fred Lange-Nielsen , working in Tønsberg , Norway .  Italian pediatrician Cesarino Romano, in 1963,  and Irish pediatrician Owen Conor Ward, in 1964,  separately described the more common variant of LQTS with normal hearing, later called Romano-Ward syndrome. The establishment of the International Long-QT Syndrome Registry in 1979 allowed numerous pedigrees to be evaluated in a comprehensive manner. This helped in detecting many of the numerous genes involved. 
An encephalopathic syndrome (characterized by weakness, lethargy , fever, tremulousness and confusion, extrapyramidal symptoms, leukocytosis , elevated serum enzymes, BUN , and fasting blood sugar) followed by irreversible brain damage has occurred in a few patients treated with lithium plus HALDOL. A causal relationship between these events and the concomitant administration of lithium and HALDOL has not been established; however, patients receiving such combined therapy should be monitored closely for early evidence of neurological toxicity and treatment discontinued promptly if such signs appear.
The influence of renal impairment on the pharmacokinetics of haloperidol has not been evaluated. About one-third of a haloperidol dose is excreted in urine, mostly as metabolites. Less than 3% of administered haloperidol is eliminated unchanged in the urine. Haloperidol metabolites are not considered to make a significant contribution to its activity, although for the reduced metabolite of haloperidol, back-conversion to haloperidol cannot be fully ruled out. Even though impairment of renal function is not expected to affect haloperidol elimination to a clinically relevant extent, caution is advised in patients with renal impairment, and especially those with severe impairment, due to the long half-life of haloperidol and its reduced metabolite, and the possibility of accumulation (see section ).