An analysis of several studies comparing low and high doses of atypical antipsychotics finds that low dose atypical antipsychotics are better for bipolar depression. In general, the therapeutic effects are the same, but side effects are significantly less with lower doses.
The study reviewed the data from seven clinical trials of high and low doses of quetiapine (4 trials), cariprazine, lurasidone, and ziprasidone (1 trial each). There were no differences between lower and higher doses of these atypical antipsychotics in terms of clinical improvement or response and remission rates. And this finding was remarkably consistent across all the studies. However, significant adverse effects were much greater in the high dose groups.
The doses studied for each atypical were:
| Atypical Antipsychotic | Low Dose | High Dose | Size of Study (s) |
| Quetiapine | 300 mg | 600 mg | 2027 (4 studies) |
| Lurasidone | 20 mg | 80 mg | 335 (1 study) |
| Ziprasidone | 40 mg | 120 mg | 362 (1 study) |
| Cariprazine | 0.75/1.5 mg | 3 mg | 436 (1 study) |
References
Bartoli F, Dell’Osso B, Crocamo C, Fiorillo A, Ketter TA, Suppes T, Clerici M, Carrà G. Benefits and harms of low and high second-generation antipsychotics doses for bipolar depression: A meta-analysis. J Psychiatr Res. 2017 Jan 1;88:38-46. doi: 10.1016/j.jpsychires.2016.12.021. [Epub ahead of print] Review. PubMed PMID: 28086127.