Pregnancy Risk Category C
How supplied
Tablets: 1 mg, 2 mg, 3 mg, 4 mg
Action
Blocks dopamine and serotonin receptors; also blocks alpha1, alpha2, and H1 receptors in the CNS.
Indications & dosage
Psychosis--
Adults: initially, 1 mg P.O. b.i.d. Increased in increments of 1 mg b.i.d. on days 2 and 3 of treatment to a target dose of 3 mg b.i.d. At least 1 week must pass before dosage is adjusted further. Safety of dosages exceeding 16 mg/day hasn't been evaluated.
Elderly: initially, 0.5 mg P.O. b.i.d. Increased in increments of 0.5 mg b.i.d. on days 2 and 3 of treatment to a target dose of 1.5 mg P.O. b.i.d. At least 1 week must pass before dosage is increased further.
Adjust-a-dose: For patients with severe renal or hepatic impairment or hypotension or in debilitated patients, initially, 0.5 mg P.O. b.i.d. Increased in increments of 0.5 mg b.i.d. on days 2 and 3 of treatment to a target dosage of 1.5 mg P.O. b.i.d. At least 1 week must pass before dosage is increased further.
Adverse reactions
CNS: somnolence, extrapyramidal symptoms, headache, insomnia, agitation, anxiety, tardive dyskinesia, aggressiveness.
CV: tachycardia, chest pain, orthostatic hypotension, prolonged QT interval.
EENT: rhinitis, sinusitis, pharyngitis, abnormal vision.
GI: constipation, nausea, vomiting, dyspepsia.
Metabolic: fever, increased serum prolactin levels.
Musculoskeletal: arthralgia, back pain.
Respiratory: coughing, upper respiratory tract infection.
Skin: rash, dry skin, photosensitivity.
Interactions
Drug-drug. Carbamazepine: increased clearance of risperidone, leading to decreased effectiveness. Monitor patient closely.
Clozapine: decreased clearance of risperidone, increasing toxicity. Monitor patient closely.
CNS depressants: additive CNS depression. Avoid concomitant use.
Levodopa: antagonized effects. Avoid concomitant use.
Drug-lifestyle. Alcohol use: additive CNS depression. Avoid concomitant use.
Sun exposure: photosensitivity reactions may occur. Take precautions.
Effects on diagnostic tests
None reported.
Contraindications
Contraindicated in patients with hypersensitivity to drug and in breast-feeding women.
Nursing considerations
Patient teaching
*Liquid contains alcohol. **May contain tartrazine. †Canada ‡Australia §U.K. OTCOver the counter
Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE-THREATENING