There are no well controlled studies with Haldol (haloperidol) in pregnant women. There are reports, however, of cases of limb malformations observed following maternal use of Haldol along with other drugs which have suspected teratogenic potential during the first trimester of pregnancy. Causal relationships were not established in these cases. Since such experience does not exclude the possibility of fetal damage due to Haldol, this drug should be used during pregnancy or in women likely to become pregnant only if the benefit clearly justifies a potential risk to the fetus.
Common adverse effects of Haldol usually include sleepiness, dizziness, rapid heart beat, constipation, excess saliva production and weight gain. Another important adverse effect that occurs commonly is orthostatic hypotension (a lowering of your blood pressure when you are sitting up or standing up). Occasionally this can lead to fainting and falling down, therefore, people taking Haldol should be careful when they change positions. These adverse effects are usually mild and usually go away after the first several days of starting treatment or increasing a dose.