474 - Prolonged and Resistant Neuroleptic Malignant Syndrome Following Long-Acting Haloperidol Injection

Friday, February 23, 2024

5:00 PM – 6:30 PM EDT

Presenting Author(s)

SS

Sahil Shah, BA

Medical Student
Rutgers New Jersey Medical School
North Brunswick, New Jersey, United States

Co-Author(s)

TA

Taylor Anthony, BA

Medical Student
Rutgers New Jersey Medical School
Newark, New Jersey, United States
MC

Mariam Chishty, MD

Resident Physician
Rutgers New Jersey Medical School
Newark, New Jersey, United States
ER

Eric Rutkowski, MD

Physician
Rutgers New Jersey Medical School
Newark, New Jersey, United States

Case Diagnosis: We present a case of refractory, prolonged Neuroleptic Malignant Syndrome (NMS) in a patient following a long-acting haloperidol injection.

Case Description: A 59-year-old female with a history of psychotic disorder presented to our facility with muscle stiffness and rigidity five days after receiving a long-acting haloperidol injection in the context of medications over objection. She presented with fever, tachycardia, labile blood pressure, elevated creatine kinase (CK), slurred speech, muscle rigidity, waxy flexibility, and dysphagia. The possibility of NMS versus catatonia was considered.

All antipsychotics were immediately held. Treatment included benzodiazepines, hydration, and supportive care during the 30-35 day haloperidol washout period. Bromocriptine was initiated on Day 10, while dantrolene and electroconvulsive therapy (ECT) were not administered. Despite stabilized vitals and decreasing CK levels, muscle rigidity persisted.

After 35 days, her rigidity and dysphagia gradually improved, with speech returning on Day 43. On Day 45, she was discharged to a subacute rehabilitation facility.

Discussions: This case underscores the refractory nature of NMS post-long-acting haloperidol injection. NMS, a rare and life-threatening complication of antipsychotics, demands prompt withdrawal, supportive care, and early intervention, including supportive measures, with consideration for the use of bromocriptine and dantrolene and potential ECT if refractory.

The delayed bromocriptine administration and the absence of escalated treatment options, such as dantrolene or ECT, may have prolonged the illness. The gradual resolution over 45 days highlights the need for early NMS recognition and intervention to prevent complications and improve outcomes.

Conclusions: This case report highlights the challenges of refractory NMS following long-acting haloperidol. Delayed treatments and the lack of dantrolene or ECT may protract the syndrome. Clinicians should vigilantly watch for NMS in antipsychotic-treated patients, ensuring prompt therapeutic measures for better outcomes and preventing life-threatening complications.