G21.0

Clinical Causes: Use of neuroleptic (antipsychotic) medications such as haloperidol, chlorpromazine, or risperidone. Rapid dose escalation or starter doses of neuroleptic drugs. Changes in medication, including drug withdrawal or switching medications. Use of other medications that interfere with dopamine pathways, contributing to susceptibility.

Key Symptoms: Muscle rigidity, often described as generalized stiffness. High fever that may develop rapidly. Altered mental status, including confusion or agitation. Autonomic dysfunction, such as rapid heartbeat, fluctuating blood pressure, excessive sweating, and drooling. Elevated levels of muscle enzymes like creatine kinase (CK), indicating muscle breakdown. Difficulty swallowing or breathing in severe cases.

Diagnosis Path: Diagnosing Malignant Neuroleptic Syndrome involves a combination of clinical evaluation and laboratory tests. Healthcare providers typically consider recent use of neuroleptic medications and assess for classic symptoms. Laboratory tests might include a blood test to measure creatine kinase levels, electrolyte panels, and other markers of muscle injury or autonomic dysfunction. Differential diagnosis also considers conditions such as serotonin syndrome or malignant hyperthermia. There are no specific tests for MNS, making clinical judgment crucial.

Treatment Protocols: Immediate management of MNS focuses on stopping neuroleptic medications and providing supportive care. Common interventions include: - **Discontinuing offending drugs** promptly. - **Monitoring vital signs** continuously and supporting cardiovascular stability. - **Cooling measures** to address high body temperature. - **Medications** such as dantrolene or bromocriptine to reduce muscle rigidity and improve dopamine function. - **Intravenous fluids** to prevent dehydration and support kidney function. - **Monitoring and correcting electrolyte imbalances**. - In severe cases, intensive care unit (ICU) admission may be necessary. Recovery depends on the promptness of treatment initiation, and some patients may require prolonged hospitalization. Prevention involves careful monitoring when starting or adjusting neuroleptic medications, especially in individuals at higher risk.