Clinical Overview
Iloperidone is an atypical antipsychotic indicated for the treatment of schizophrenia in adults and acute treatment of manic or mixed episodes associated with bipolar I disorder. It offers a unique receptor binding profile with potentially lower risk of extrapyramidal symptoms compared to typical antipsychotics.
Primary Clinical Applications
Iloperidone is effective for both positive and negative symptoms of schizophrenia and has demonstrated efficacy in acute manic episodes of bipolar I disorder. Its balanced receptor profile may provide antipsychotic efficacy while minimizing movement-related side effects.
Mechanism and Pharmacological Profile
Iloperidone antagonizes dopamine D2 and D3 receptors, serotonin 5-HT2A receptors, and has affinity for norepinephrine alpha-1 adrenergic receptors. This receptor profile contributes to its antipsychotic efficacy while potentially reducing extrapyramidal side effects compared to typical antipsychotics.
Dosing and Tolerability
Iloperidone requires slow dose titration over the first week to minimize orthostatic hypotension. The gradual titration schedule is essential for tolerability, particularly regarding cardiovascular effects. Once stabilized, most patients achieve therapeutic benefit in the 6-12 mg twice daily range.
Prescribing Information
Dosing & Administration
Schizophrenia – Adults:
- Day 1: 1 mg twice daily
- Day 2: 2 mg twice daily
- Day 3: 4 mg twice daily
- Day 4: 6 mg twice daily
- Day 5-7: 8 mg twice daily
- Target range: 6-12 mg twice daily
- Maximum: 12 mg twice daily
Bipolar I Disorder (Manic/Mixed Episodes):
- Same titration schedule as schizophrenia
- Effective range: 6-12 mg twice daily
Administration:
- Take with or without food
- Titration schedule must be followed to minimize orthostatic hypotension
Indications
- Treatment of schizophrenia in adults
- Note: Bipolar I disorder is not an FDA-approved indication in the US
Contraindications
- Hypersensitivity to iloperidone or any component
- No absolute contraindications, but caution in cardiovascular disease
Warnings & Precautions
- Boxed Warning: Increased mortality in elderly patients with dementia-related psychosis
- QT prolongation: Monitor ECG in patients with cardiac risk factors
- Orthostatic hypotension: Slow titration required, monitor blood pressure
- Neuroleptic malignant syndrome: Rare but serious risk
- Tardive dyskinesia: Risk with long-term use
- Metabolic changes: Monitor glucose, lipids, and weight
Drug Interactions
- Strong CYP2D6 inhibitors: Reduce iloperidone dose by 50%
- Strong CYP3A4 inhibitors: Reduce iloperidone dose by 50%
- CYP2D6 poor metabolizers: Reduce dose by 50%
- QT-prolonging drugs: Use caution, monitor ECG
Adverse Reactions
Common (≥5%):
- Dizziness, dry mouth, fatigue, nasal congestion
- Orthostatic hypotension, weight gain, tachycardia
Metabolic:
- Weight gain, hyperglycemia, dyslipidemia
Cardiovascular:
- QT prolongation, orthostatic hypotension
Special Populations
- CYP2D6 poor metabolizers: Reduce dose by 50%
- Hepatic impairment: Use caution, may require dose reduction
- Renal impairment: No specific dose adjustment recommended
- Elderly: Increased mortality risk in dementia-related psychosis
- Pregnancy: Category C – use only if benefits outweigh risks
Medical Disclaimer: This information is for educational purposes only and is not intended as medical advice. Always consult with qualified healthcare professionals before making any treatment decisions. Individual patient circumstances may vary significantly.
