Mental health articles

Typical antipsychotics

Mechanism of action

 Extensive research was undertaken into the mechanisms of action of typical antipsychotics. This has led to the development of a range of theories regarding the pathology of psychosis. Over time, it became clear that it was the ability to act as a dopamine antagonist that produced the clinically desirable effect, and by 1993 McKay and McKenna were confi dent in stating: ‘In short, that the antipsychotic effects of neuroleptic drugs is a consequence of the ability to block dopamine receptors must be regarded as established beyond reasonable doubt.’ McKay & McKenna  However, dopamine blockade serves merely to ameliorate the positive symptoms of psychosis, such as auditory hallucinations, delusions and paranoia, which often persist at a residual, albeit more tolerable, level. Positive symptom reduction is thought to derive from the blockade of dopamine D2 receptors in the meso-limbic system. The therapeutic effect takes time to develop and full response may take several weeks. Side effects, however, emerge immediately. In an acute phase, rapid acting adjunctive treatment such as a benzodiazepine to reduce distress and ensure safety should be considered.

Tags: action, antipsychotics, mechanism, typical antipsychotics