neuroleptic malignant syndrome

Last reviewed 01/2018

Malignant neuroleptic syndrome is a rare, potentially fatal idiosyncratic reaction occurring in response to neuroleptic drug therapy. It has been reported for haloperidol, chlorpromazine and flupenthixol decanoate.

The syndrome lasts 5-10 days after the discontinuation of drug therapy during which time ITU support is necessary (1)

There is no proven treatment though bromocriptine and dantrolene have been used.

This syndrome can also occur in patients with Parkinson's disease following withdrawal of levodopa or dopamine antagonists or by the addition of lithium (2).

Reference:

• (1) BMJ editorial (1993). How "malignant" is the neuroleptic malignant syndrome.BMJ, 307, 1223-4.
• (2) Prescriber (2001), 12 (5), 43-8.