[1 mg tablets 34 cents]
- PO, IM
- Ridal, Risperidal
- agitation and delirium
PRESENTATION AND ADMINISTRATION:
Long-acting Depot ONLY (not for use in ICU)
Ridal 0.5mg (red), 1mg (white), 2mg (orange), 3mg (yellow), 4mg (green)
Risperidal 0.5mg (brownish / red), 1mg (white), 2mg (orange), 3mg (yellow), 4mg (green)
Oral Disintegrating Tablets:
Risperdal Quicklet 0.5mg (light coral), 1mg (light coral), 2mg (coral)
Oral Solution: Risperdal Solution 1mg/ml
0.5-1mg 12 hourly; increase to a maximum of 8mg 12 hourly
DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:
- Dose in renal impairment [GFR (ml/min)]:
<10: initial dose of 0.5mg, increase slowly to 1-2mg BD
10-20: initial dose of 0.5mg, increase slowly to 1-2mg BD
>20-50: initial dose of 0.5mg, increase slowly to 1-2mg BD
- Dose in renal replacement therapy:
CAPD: initial dose of 0.5mg, increase slowly to 1-2mg BD
HD: initial dose of 0.5mg, increase slowly to 1-2mg BD
CVVHDF: initial dose of 0.5mg, increase slowly to 1-2mg BD
DOSAGE IN PAEDIATRICS:
- 0.02mg/kg 12 hourly; increase to 0.15mg/kg 12 hourly
- Risperidone is a compound which belongs to a new class of antipsychotic agents, the benzisoxazole derivatives. Risperidone is a selective monoaminergic antagonist having a high affinity for serotoninergic 5-HT2 and dopaminergic D2 receptors. Risperidone binds also to alpha1-adrenergic receptors and, with lower affinity, to H1-histamine and alpha2-adrenergic receptors.
- sensitivity to risperidone
- Increased risk of deaths in patients with dementia:
Elderly patients with dementia-related psychosis treated with atypical antipsychotic drugs are at an increased risk of death compared to placebo.
- Hyperglycemia and Diabetes Mellitus:
Hyperglycemia, in some cases extreme and associated with ketoacidosis or hyperosmolar coma or death, has been reported in patients treated with atypical antipsychotics including risperidone.
- Neuroleptic Malignant Syndrome (NMS):
A potentially fatal symptom complex sometimes referred to as Neuroleptic Malignant Syndrome (NMS) has been reported in association with administration of antipsychotic drugs, including risperidone.
- Tardive Dyskinesia: A syndrome of potentially irreversible, involuntary, dyskinetic movements may develop in patients treated with antipsychotic drugs.
Risperidone may induce hypotension.
Classical neuroleptics are known to lower the seizure threshold. Caution is recommended when treating patients with epilepsy.
- Laboratory Tests: No tests additional to routine ICU tests are indicated
- Drug/Laboratory Test Interactions: None reported
IMPORTANT DRUG INTERACTIONS FOR THE ICU
- Given the primary CNS effects of risperidone, it should be used with caution in combination with other centrally-acting medicines. Carbamazepine has been shown to decrease the plasma levels of the active antipsychotic fraction of risperidone. On discontinuation of carbamazepine the dosage of risperidone should be re-evaluated and, if necessary, decreased.
- Cardiovascular System: Hypotension, Tachycardia, Hypertension
- Digestive System: Dry mouth, Constipation, Dyspepsia, Vomiting
- Nervous System: Somnolence, Dizziness, Tremor, Hypertonia
- Haematological System: Decreased neutrophil count, decreased platelet count