RESUMO
OBJECTIVE: To report a case of delayed-onset dystonic reactions, oculogyric crisis (OGC), and torticollis after treatment with intramuscular haloperidol lactate injection. CASE SUMMARY: A 22-year-old Mexican American woman received intramuscular haloperidol lactate 7.5 mg followed 4 hours later by 10 mg. Twenty-six hours after the first injection, the patient reported that she was unable to lower her gaze and that her neck was stiff. She was immediately given intramuscular benztropine 2 mg; there was a nearly complete remission of symptoms within 15 minutes of treatment. An objective causality assessment revealed a probable relationship between the OGC/torticollis and haloperidol therapy. DISCUSSION: Dystonic reactions have been reported in 10-60% of patients treated with neuroleptic medication, most commonly when patients just start or increase the dose of the drug. The highest frequency of dystonic reactions has occurred in patients receiving high-potency neuroleptics. It has also been suggested that haloperidol-induced dystonic reactions are a result of the toxic metabolites of that agent. CONCLUSIONS: OGC and torticollis reactions may occur 12-24 hours after treatment with a high-potency neuroleptic, even in the absence of symptoms of extrapyramidal side effects (EPSEs). The delayed dystonic reaction may begin suddenly (no early EPSE symptomatology).