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risperidone
Risperdal

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

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