[Protracted recurrent neuroleptic malignant syndrome]
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Abstract:
The natural course of untreated neuroleptic malignant syndrome (NMS) does not usually exceed 3 weeks. Its duration is reduced by dantrolene and/or bromocriptine. We report a patient in whom NMS developed after an injection of haloperidol decanoate and fluctuated during 3 months. This was due perhaps because the initial treatment with oral neuroleptic was pursued, or because the doses of dantrolene were insufficient.
Insights
Neuroleptic Malignant Syndrome (NMS) typically resolves within 3 weeks. This case study details a prolonged 3-month NMS episode, possibly due to ongoing oral neuroleptic treatment or inadequate dantrolene dosage.
Area of Science:
- Neuroscience
- Pharmacology
- Clinical Medicine
Background:
- Neuroleptic Malignant Syndrome (NMS) is a rare but serious adverse reaction to antipsychotic medications.
- The typical duration of untreated NMS is generally limited to three weeks.
- Pharmacological interventions like dantrolene and bromocriptine are known to shorten NMS duration.
Observation:
- This report describes an unusual case of NMS that persisted for three months.
- The NMS episode occurred following an injection of haloperidol decanoate, a long-acting antipsychotic formulation.
- The patient's NMS symptoms fluctuated over the extended period.
Findings:
- The prolonged NMS duration in this patient deviated significantly from the typical clinical course.
- Potential contributing factors identified include the concurrent administration of oral neuroleptics and potentially insufficient doses of dantrolene.
- This case highlights the complexity of managing NMS, especially with long-acting injectable antipsychotics.
Implications:
- This case suggests that continued exposure to oral neuroleptics may prolong NMS, even with long-acting injectable administration.
- The findings underscore the importance of optimizing dantrolene dosage and duration in managing prolonged NMS cases.
- Further research is warranted to understand the factors contributing to atypical NMS chronicity and to refine treatment guidelines.
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