Absorption: 70% after administration of tablets, solution, or orally disintegrating tablets. Following IM administration, small initial release of drug, followed by 3-wk lag; the rest of release starts at 3 wk and lasts 4–6 wk. Following subcutaneous administration, initial release of drug occurs at 4–6 hr, with the rest of release occurring at 10–14 days after administration.
Distribution: Unknown.
Metabolism/Excretion: Primarily metabolized by the liver by the CYP2D6 isoenzyme to 9–hydroxyrisperidone (has similar pharmacological properties as risperidone). Risperidone and its active metabolite are renally eliminated.
Half-life: Extensive metabolizers — 3 hr for risperidone, 21 hr for 9-hydroxyrisperidone. Poor metabolizers — 20 hr for risperidone and 30 hr for 9-hydroxyrisperidone; Subcutaneous — 9–11 days.
CV: arrhythmias, orthostatic hypotension, tachycardia.
Derm: STEVENS-JOHNSON SYNDROME, TOXIC EPIDERMAL NECROLYSIS, itching/skin rash, dry skin, ↑ pigmentation, sweating, photosensitivity, seborrhea.
EENT: pharyngitis, rhinitis, visual disturbances.
Endo: dyslipidemia, galactorrhea, hyperglycemia.
GI: constipation, diarrhea, dry mouth, nausea, abdominal pain, anorexia, dyspepsia, dysphagia, polydipsia, ↑ salivation, vomiting.
GU: ↓libido, dysmenorrhea/menorrhagia, amenorrhea, difficulty urinating, gynecomastia, ↓ fertility (females), impotence, polyuria, priapism.
Hemat: AGRANULOCYTOSIS, leukopenia, neutropenia.
Metab: weight gain, weight loss.
MS: arthralgia, back pain.
Neuro: NEUROLEPTIC MALIGNANT SYNDROME, SEIZURES, aggressive behavior, dizziness, extrapyramidal reactions, headache, ↑dreams, ↑sleep duration, insomnia, sedation, fatigue, impaired temperature regulation, nervousness, tardive dyskinesia.
Resp: cough, dyspnea.
Misc: HYPERSENITIVITY REACTIONS (INCLUDING ANAPHYLAXIS AND ANGIOEDEMA).
Schizophrenia
- PO (Adults): 1 mg twice daily, ↑ by 1–2 mg/day no more frequently than every 24 hr to 4–8 mg daily.
- PO (Children 13–17 yr): 0.5 mg once daily, ↑ by 0.5–1.0 mg no more frequently than every 24 hr to 3 mg daily. May administer half the daily dose twice daily if drowsiness persists.
- IM (Adults): 25 mg every 2 wk; some patients may benefit from a higher dose of 37.5 or 50 mg every 2 wk.
- SC (Adults): Currently taking 3 mg/day of oral risperidone — 90 mg once monthly; Currently taking 4 mg/day of oral risperidone — 120 mg once monthly; Planned therapy with fluoxetine or paroxetine — Initiate 90 mg once monthly 2–4 wk before starting fluoxetine or paroxetine therapy; Concurrent use of strong CYP3A4 inducer — If receiving 90 mg once monthly regimen, consider ↑ dose to 120 mg once monthly; if receiving 120 mg once monthly regimen, consider using additional oral risperidone.
Hepatic Impairment
- PO (Adults): Severe renal impairment (CCr <30 mL/min) or severe hepatic impairment — Start with 0.5 mg twice daily; ↑ by 0.5 mg twice daily, up to 1.5 mg twice daily; then ↑ at weekly intervals if necessary.
Hepatic Impairment
- SC (Adults): Titrate patients up to at least 3 mg/day of oral risperidone before initiating subcutaneous risperidone. If patient tolerates this dose of oral risperidone, consider subcutaneous dose of 90 mg once monthly.
Acute Manic or Mixed Episodes Associated with Bipolar I Disorder
- PO (Adults): 2–3 mg/day as a single daily dose, dose may be ↑ at 24-hr intervals by 1 mg (range 1–5 mg/day).
- PO (Children 13–17 yr): 0.5 mg once daily, ↑ by 0.5–1 mg no more frequently than every 24 hr to 2.5 mg daily. May administer half the daily dose twice daily if drowsiness persists.
- PO (Geriatric Patients or Debilitated Patients): Start with 0.5 mg twice daily; ↑ by 0.5 mg twice daily, up to 1.5 mg twice daily; then ↑ at weekly intervals if necessary. May also be given as a single daily dose after initial titration.
Hepatic Impairment
- PO (Adults): Severe renal impairment (CCr <30 mL/min) or severe hepatic impairment — Start with 0.5 mg twice daily; ↑ by 0.5 mg twice daily, up to 1.5 mg twice daily; then ↑ at weekly intervals if necessary.
Maintenance Treatment of Bipolar I Disorder
- IM (Adults): 25 mg every 2 wk; some patients may benefit from a higher dose of 37.5 or 50 mg every 2 wk.
Irritability Associated with Autistic Disorder
- PO (Children 5–16 yr weighing <20 kg): 0.25 mg/day initially. After at least 4 days of therapy, may ↑ to 0.5 mg/day. Dose ↑ in increments of 0.25 mg/day may be considered at 2 wk or longer intervals. May be given as a single or divided dose.
- PO (Children 5–16 yr weighing >20 kg): 0.5 mg/day initially. After at least 4 days of therapy, may ↑ to 1 mg/day. Dose ↑ in increments of 0.5 mg/day may be considered at 2 wk or longer intervals. May be given as a single or divided dose.
Hepatic Impairment
- PO (Adults): Severe renal impairment (CCr <30 mL/min) or severe hepatic impairment — Start with 0.5 mg twice daily; ↑ by 0.5 mg twice daily, up to 1.5 mg twice daily; then ↑ at weekly intervals if necessary.
Perseris, RisperDAL, RisperDAL Consta, RisperDAL M-TAB
Therapeutic Classification: antipsychotics
Pharmacologic Classification: benzisoxazoles
