Adaptive changes to antipsychotics: How to avoid the consequences

Take-home points

Adaptive upregulation of dopamine neuro­transmission underlies acute adverse effects such as parkinsonism and is also key for delayed consequences such as TD, and possibly the development of treatment resistance. Adaptive upregulation results from an increase in postsynaptic dopamine receptors, numbers of synapses, and dopamine release. The latter has been demonstrated to be greatest with full antagonists, less with partial agonists, and not present with lumateperone, which is a postsynaptic antagonist but a presynaptic partial agonist (Figure²⁷). Reducing adaptive upregulation can reduce both acute and long-term consequences of dopamine blockade. Early use of agents that minimize these adaptive changes, such as a postsynaptic partial agonist (aripiprazole, brexpiprazole, or cariprazine) or a presynaptic partial agonist (lumateperone), appears to be a reasonable clinical option.

Bottom Line

Chronic dopamine D2 receptor blockade with antipsychotics induces adaptive changes that can contribute to both acute and chronic adverse effects. The most severe of these are tardive dyskinesia (TD) and dopamine supersensitivity psychosis (DSP). The use of agents that mitigate these changes, such as the partial D2 agonists aripiprazole, brexpiprazole, and cariprazine and the postsynaptic antagonist/presynaptic partial agonist lumateperone, can potentially reduce these adaptive changes and reduce the likelihood of TD and DSP.

Related Resources

• Citrome L. Aripiprazole, brexpiprazole, and cariprazine: not all the same. Current Psychiatry. 2018;17(4):24-33,43.
• Meyer JM. Lumateperone for schizophrenia. Current Psychiatry. 2020;19(2):33-39.

Drug Brand Names

Aripiprazole • Abilify
Brexpiprazole • Rexulti
Cariprazine • Vraylar
Haloperidol • Haldol
Lumateperone • Caplyta
Methamphetamine • Desoxyn
Risperidone • Risperdal