Side effects that may go away during treatment, include drowsiness, dizziness, nasal congestion, blurred vision, dry mouth, or constipation. If they continue or are bothersome, check with your doctor. CHECK WITH YOUR DOCTOR AS SOON AS POSSIBLE if you experience changes in vision; changes in breasts; changes in menstrual period; sore throat; inability to move eyes; muscle spasms of face, neck, or back; difficulty swallowing; mask-like face; tremors of hands; restlessness; tension in legs; shuffling walk or stiff arms or legs; puffing of cheeks; lip smacking or puckering; twitching or twisting movements; or weakness of arms or legs.
Given these considerations, antipsychotic drugs should be prescribed in a manner that is most likely to minimize the occurrence of tardive dyskinesia. Chronic antipsychotic treatment should generally be reserved for patients who suffer from a chronic illness that 1) is known to respond to antipsychotic drugs, and 2) for whom alternative, equally effective, but potentially less harmful treatments are not available or appropriate. In patients who do require chronic treatment, the smallest dose and the shortest duration of treatment producing a satisfactory clinical response should be sought. The need for continued treatment should be reassessed periodically.
The smallest amount that will produce the desired results must be carefully determined for each individual, since optimal dosage levels of this potent drug may vary from patient to patient. In general, the oral dose has been found to be approximately two to three times the parenteral dose of fluphenazine. Treatment is best instituted with a low initial dosage, which may be increased, if necessary, until the desired clinical effects are achieved. Therapeutic effect is often achieved with doses under 20 mg daily. Patients remaining severely disturbed or inadequately controlled may require upward titration of dosage. Daily doses up to 40 mg may be necessary; controlled clinical studies have not been performed to demonstrate safety of prolonged administration of such doses.