The term “neuroleptic” is an older classification for medications more commonly known today as antipsychotics. First developed in the 1950s, these prescription drugs are designed to manage symptoms associated with psychosis, a condition where an individual has a disconnected perception of reality. Their primary function is to alleviate these distressing symptoms and help stabilize a person’s mood and thinking.
Medical Uses of Neuroleptics
Neuroleptic medications are approved to treat psychiatric disorders characterized by psychotic symptoms. Their main application is in managing schizophrenia, a condition that can involve hallucinations, delusions, and severely disorganized thought and speech. They are also a standard treatment for the manic episodes associated with bipolar disorder, helping to calm agitation and curb impulsive behaviors.
Beyond these primary uses, neuroleptics are frequently prescribed “off-label” to address symptoms in other conditions. For instance, they may be used to manage severe agitation in individuals with dementia or to augment treatment for major depressive disorder. Clinicians may also use them to control the tics associated with Tourette syndrome or to reduce irritability in some individuals with autism spectrum disorder.
How Neuroleptics Affect the Brain
Neuroleptic medications alter the activity of neurotransmitters, primarily dopamine. A long-standing theory, the “dopamine hypothesis,” suggests that an overactivity of dopamine pathways in certain brain regions contributes to the symptoms of psychosis, such as hallucinations and delusions.
These drugs work by blocking specific dopamine receptors, particularly the D2 receptor subtype. By attaching to these receptors without activating them, neuroleptics prevent dopamine from binding and sending its signals. This action reduces the excessive dopamine traffic in key brain circuits, which helps to alleviate the disruptive symptoms of psychosis.
Classification of Neuroleptics
Neuroleptics are broadly categorized into two main groups: first-generation and second-generation medications. The first-generation, or “typical” neuroleptics, were the first to be developed in the 1950s. These drugs, such as Haloperidol, primarily function by blocking dopamine receptors throughout the brain. Their widespread action is effective at managing psychosis but also leads to a higher risk of certain side effects.
Second-generation, or “atypical” neuroleptics, became more common in the 1990s. Medications like Risperidone and Olanzapine fall into this category. Atypicals differ from typicals as they block dopamine receptors more selectively and also influence serotonin receptors. This dual action is believed to contribute to their effectiveness and is associated with a different profile of potential side effects.
Potential Side Effects
Neuroleptic medications can be accompanied by potential side effects, which vary depending on the drug and individual. One of the most recognized groups involves movement. Extrapyramidal symptoms (EPS) can occur, manifesting as muscle stiffness, tremors, and restlessness. A more serious, long-term risk is tardive dyskinesia (TD), a condition characterized by involuntary, repetitive body movements that can be irreversible.
Metabolic changes are another significant concern, particularly with second-generation neuroleptics. These medications can lead to considerable weight gain, elevated blood sugar levels, and an increase in cholesterol and triglycerides. Such changes can heighten the risk of developing type 2 diabetes and other metabolic syndromes. Other common effects include sedation, dizziness, and dry mouth.
A rare but dangerous reaction to neuroleptics is Neuroleptic Malignant Syndrome (NMS). This medical emergency is identified by a combination of high fever, severe muscle rigidity, confusion, and autonomic instability, such as fluctuating blood pressure and a rapid heartbeat. NMS requires immediate medical intervention. Given the wide array of possible side effects, ongoing communication with a healthcare provider is important.