Your response indicates that this patient is receiving a bioavailable dose of the present neuroleptic. If you were to increase the oral dose, this might help a little with the psychosis, especially in the acutely ill patient who is being influenced by intense paranoid ideation, but this slight improvement probably would come at considerable cost in terms of side effects.¹ Most studies actually show no benefit to higher doses beyond 5-10 mg of haloperidol² or equivalent dosage with the other five drugs in the "standard-typical" list. The presence of parkinsonism indicated that you are at a dose which gives you the maximum benefit to risk ratio.
Note that in the elderly, in female patients, in Asian individuals,³ and in some mentally retarded patients with brain damage, the bioavailable dosage might be even lower than 5 to 10 mg of haloperidol equivalents. The clinical significance (ie - that there is little to be gained from increasing the dose) should be the same.
