Invega Sustenna is an extended-release antipsychotic medication primarily used to treat schizophrenia and schizoaffective disorder in adults. It contains paliperidone palmitate and is administered via intramuscular injection. Typically, after the initial doses, it is given once a month, but in some cases, it can be prescribed every three weeks. This medication helps manage symptoms by restoring the balance of certain natural substances in the brain.
Dosage and Administration
Invega Sustenna 234 mg is administered as an intramuscular injection. Here’s the specific dosage regimen and important considerations:
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Administration:
- Intramuscular Injection: Administered only by a healthcare professional.
- Injection Sites: Deltoid or gluteal muscle.
- Needle Size:
- Deltoid: 1-inch, 23 gauge needle for patients <90 kg; 1½-inch, 22 gauge needle for patients ≥90 kg.
- Gluteal: 1½-inch, 22 gauge needle regardless of weight.
- Injection Technique: Inject slowly and deep into the muscle, alternating between the two deltoid or gluteal muscles.
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Dosage Regimen:
- Initial Dose: 234 mg on day 1.
- Second Dose: 156 mg one week later.
- Maintenance Dose: Monthly injections of 39 mg to 234 mg, depending on individual needs.
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Important Considerations:
- Tolerability: Establish tolerability with oral paliperidone or risperidone before starting Invega Sustenna.
- Missed Doses: Follow specific guidelines for managing missed doses.
- Renal Impairment: Adjust dosage for patients with mild renal impairment; not recommended for moderate to severe renal impairment.
Mechanism of Action
Invega Sustenna (paliperidone palmitate) is an atypical antipsychotic. It primarily works by affecting the levels of dopamine and serotonin in the brain. Here’s a concise breakdown of its pharmacological effects:
- Dopamine D2 Receptor Antagonism: Invega Sustenna blocks dopamine D2 receptors, which helps reduce symptoms of psychosis such as hallucinations and delusions.
- Serotonin 5-HT2A Receptor Antagonism: It also blocks serotonin 5-HT2A receptors, which can help improve mood and reduce anxiety.
- Extended-Release Mechanism: The medication is formulated as an extended-release injectable suspension, allowing for a steady release of the drug over three weeks.
- Metabolism: Paliperidone is the active metabolite of risperidone, and it is primarily excreted unchanged in the urine.
This combination of actions helps manage symptoms of schizophrenia and schizoaffective disorder effectively.
Efficacy
Invega Sustenna (paliperidone palmitate), administered at 234 mg every 3 weeks, has shown significant effectiveness in treating schizophrenia and schizoaffective disorder. Clinical studies have demonstrated its efficacy in delaying relapse and reducing overall relapse rates compared to daily oral antipsychotics.
- Time to Relapse: In a long-term study, Invega Sustenna significantly extended the time to relapse compared to placebo, leading to the study’s early termination due to its efficacy.
- Relapse Reduction: Another study highlighted that Invega Sustenna delayed relapse (hospitalization, arrest, incarceration) by six months longer than commonly prescribed oral antipsychotics.
- Efficacy in Schizophrenia: In a randomized, 13-week study, patients receiving Invega Sustenna showed significant improvement in symptoms compared to placebo.
These findings underscore the effectiveness of Invega Sustenna in managing symptoms and preventing relapse in patients with schizophrenia and schizoaffective disorder.
Side Effects
Sure, here are the potential side effects of Invega Sustenna (234 mg every 3 weeks):
Common Side Effects:
- Drowsiness and Dizziness: These can increase the risk of falls, especially when getting up from a sitting or lying position.
- Weight Gain: This can be significant and may also lead to increased cholesterol levels.
- Injection Site Reactions: Pain, redness, and swelling at the injection site.
- Headache: A frequent complaint among users.
- Upper Respiratory Tract Infections: Such as colds and sinus infections.
- Restlessness or Difficulty Sitting Still: Known as akathisia.
- Stiffness and Shuffling Walk: Symptoms of parkinsonism.
- Tremors: Uncontrolled shaking, often in the hands.
Serious Side Effects:
- Neuroleptic Malignant Syndrome (NMS): Symptoms include high fever, muscle stiffness, confusion, sweating, and irregular heartbeat. This is a medical emergency.
- Tardive Dyskinesia: Involuntary, repetitive body movements, which may be permanent.
- High Blood Sugar (Hyperglycemia): Can lead to or worsen diabetes.
- Increased Prolactin Levels: Can cause breast enlargement, milk production, and menstrual irregularities in women, and decreased sexual ability in men.
- Low White Blood Cell Count: Increases the risk of infections.
- Severe Allergic Reactions: Symptoms include rash, itching/swelling, severe dizziness, and trouble breathing.
- Heart Issues: Irregular heartbeat, chest pain, and fainting.
If you experience any of these side effects, it’s important to contact your healthcare provider immediately. They can help manage these reactions and adjust your treatment if necessary.
Patient Considerations
Here are the key considerations for patients receiving Invega Sustenna 234 mg every 3 weeks:
Contraindications
- Hypersensitivity: Known hypersensitivity to paliperidone, risperidone, or any components in the formulation.
Precautions
- Elderly Patients with Dementia-Related Psychosis: Increased risk of mortality; not approved for this use.
- Neuroleptic Malignant Syndrome (NMS): Immediate discontinuation and close monitoring required.
- QT Prolongation: Avoid use with other QT-prolonging drugs and in patients with risk factors.
- Tardive Dyskinesia: Discontinue if clinically appropriate.
- Metabolic Changes: Monitor for hyperglycemia, diabetes mellitus, dyslipidemia, and weight gain.
- Orthostatic Hypotension and Syncope: Monitor heart rate and blood pressure, especially in patients with cardiovascular or cerebrovascular disease.
Monitoring Requirements
- Glucose Levels: Regular monitoring in patients with or at risk for diabetes.
- Cardiovascular Health: Monitor heart rate and blood pressure.
Invega Sustenna 234 mg: An Extended-Release Antipsychotic Medication
Invega Sustenna 234 mg administered every three weeks is an extended-release antipsychotic medication primarily used to treat schizophrenia and schizoaffective disorder in adults.
It contains paliperidone palmitate, which helps manage symptoms by restoring the balance of certain natural substances in the brain. The medication is given via intramuscular injection, typically once a month, but can be prescribed every three weeks in some cases.
Efficacy and Effectiveness
Invega Sustenna has shown significant effectiveness in treating schizophrenia and schizoaffective disorder, with clinical studies demonstrating its efficacy in delaying relapse and reducing overall relapse rates compared to daily oral antipsychotics.
Common Side Effects
However, it may cause common side effects such as:
- drowsiness
- weight gain
- injection site reactions
- headache
- upper respiratory tract infections
- restlessness
- stiffness
- tremors
Serious Side Effects
and serious side effects like:
- neuroleptic malignant syndrome
- tardive dyskinesia
- high blood sugar
- increased prolactin levels
- low white blood cell count
- severe allergic reactions
- heart issues
Monitoring and Precautions
Patients receiving Invega Sustenna 234 mg every three weeks should be monitored for glucose levels, cardiovascular health, and other potential side effects.
