Typical Antipsychotics

Summary

Typical or first-generation antipsychotics are an older class of medications used to treat psychosis, particularly the positive symptoms of schizophrenia, such as delusions and hallucinations.

These drugs are categorized into high-potency and low-potency agents. High-potency antipsychotics include haloperidol, fluphenazine, pimozide, and trifluoperazine. While effective in managing symptoms of psychosis, these drugs are more likely to cause neurological side effects.

On the other hand, low-potency antipsychotics, like thioridazine and chlorpromazine, are associated with fewer neurological side effects but come with their own unique risks. Notably, thioridazine can cause retinal deposits, while chlorpromazine can lead to corneal deposits, potentially affecting vision.

Key Points

• Typical (1st-generation) Antipsychotics
  • Unique Clinical Uses
    • Treat positive symptoms only (in schizophrenia)
      • Positive symptoms include delusions, hallucinations, thought disorders
      • Has minimal effect on negative symptoms (flat affect, apathy, anhedonia, minimal speech, anti-social behavior)
      • Not considered first-line due to above
  • Unique Mechanisms
    • Stronger D2 receptor antagonism than atypical antipsychotics
      • More likely to cause hyperprolactinemia, extrapyramidal symptoms, and neuroleptic malignant syndrome
  • Drug Names
    • High potency
      • More likely to cause extrapyramidal symptoms, neuroleptic malignant syndrome, and hyperprolactinemia
      • Haloperidol
      • Fluphenazine
      • Pimozide
    • Low potency
      • More likely to cause antihistaminic, alpha-1 blocking, and anticholinergic effects
      • Chlorpromazine
        • Causes corneal deposits
      • Thioridazine
        • Causes retinal deposits
      • Trifluoperazine