THERAPEUTICS

Brands

• Mellaril
• see index for additional brand names

Generic?

• Yes

Class

• Conventional antipsychotic (neuroleptic, phenothiazine, dopamine 2 antagonist)

Commonly Prescribed for

• (bold for FDA approved)
• Schizophrenic patients who fail to respond to treatment with other antipsychotic drugs

How the Drug Works

• Blocks dopamine 2 receptors, reducing positive symptoms of psychosis

How Long Until It Works

• Psychotic symptoms can improve within 1 week, but it may take several weeks for full effect on behavior

If It Works

• Is a second-line treatment option
• Should evaluate for switching to an antipsychotic with a better risk/benefit ratio

If It Doesn’t Work

• Consider trying one of the first-line atypical antipsychotics (risperidone, olanzapine, quetiapine, ziprasidone, aripiprazole,paliperidone, amisulpride)
• Consider trying another conventional antipsychotic
• If 2 or more antipsychotic monotherapies do not work, consider clozapine

Best Augmenting Combos for Partial Response or Treatment Resistance

• Augmentation of thioridazine has not been systematically studied and can be dangerous, especially with drugs that can either prolong QTc interval or raise thioridazine plasma levels

Tests

• Baseline EKG and serum potassium levels should be determined
• Periodic evaluation of EKG and serum potassium levels
• Serum magnesium levels may also need to be monitored
• Since conventional antipsychotics are frequently associated with weight gain, before starting treatment, weigh all patients and determine if the patient is already overweight (BMI 25.0–29.9) or obese (BMI ≥30)
• Before giving a drug that can cause weight gain to an overweight or obese patient, consider determining whether the patient already has pre-diabetes (fasting plasma glucose 100–25 mg/dL), diabetes (fasting plasma glucose >126 mg/dL), or dyslipidemia (increased total cholesterol, LDL cholesterol and triglycerides; decreased HDL cholesterol), and treat or refer such patients for treatment, including nutrition and weight management, physical activity counseling, smoking cessation, and medical management
• Monitor weight and BMI during treatment
• Consider monitoring fasting triglycerides monthly for several months in patients at high risk for metabolic complications and when initiating or switching antipsychotics
• While giving a drug to a patient who has gained >5% of initial weight, consider evaluating for the presence of pre-diabetes, diabetes, or dyslipidemia, or consider switching to a different antipsychotic
• Should check blood pressure in the elderly before starting and for the first few weeks of treatment
• Monitoring elevated prolactin levels of dubious clinical benefit
• Phenothiazines may cause false-positive phenylketonuria results
• Patients with low white blood cell count (WBC) or history of drug-induced leucopenia/neutropenia should have complete blood count (CBC) monitored frequently during the first few months and thioridazine should be discontinued at the first sign of decline of WBC in the absence of other causative factors