Although the newer generation of antipsychotic drugs, or neuroleptics, have fewer negative side effects than the older generations, a new study has found that higher doses are needed during pregnancy to maintain a therapeutic effect.
Researchers from the University Department of Paediatrics and Adolescent Medicine at the Medical University of Vienna investigated the pharmacological changes of a new generation of neuroleptics in pregnant women.
Neuroleptics are often prescribed when symptoms are very distressing for the patient, or if the person is considered to be a danger to himself or to others. They are able to reduce hallucinations, delusions, paranoia, confusion, and other symptoms of psychosis.
Left untreated, pregnant women with psychosis are exposed to stress that can harm them and their unborn child. In this case, relapses of the condition (up to 70 percent of untreated cases) often result in abuse of drugs and alcohol and an increased risk of suicide.
However, in order to avoid risks to the unborn child, physicians often reduce the dose of neuroleptic drugs in pregnant women with psychosis. This increases the risk, however, that the level of medication will fall below the therapeutic range.
For the study, researchers measured levels of aripiprazole in blood plasma and in the umbilical cord blood of three pregnant women. The results showed that these levels fell below the therapeutic range from the middle of the pregnancy onwards due to physiological changes.
“This study shows for the first time that the dynamics of the plasma level corresponds to that of other substance classes such as antidepressants, for example,” said study leader Dr. Claudia Klier.
“Here too, the dose frequently has to be increased in order to cross back over into the effective range.”
This is the first time the transfer rate of aripiprazole across the placenta has been investigated, since clinical trials are not performed on pregnant women. There are only a few cases in which investigations have been carried out in the interests of clinical decision-making.
These cases, which have provided urgently needed safety and effectiveness data, are currently being collected from pregnant women on this new generation of neuroleptics. All three women in the study gave birth to healthy children.
Source: Medical University of Vienna