Classifications: psychotherapeutic; antipsychotic; butyrophenone; Therapeutic: antipsychotic
Pregnancy Category: C
0.5 mg, 1 mg, 2 mg, 5 mg, 10 mg, 20 mg tablets; 2 mg/mL oral solution; 5 mg/mL, 50 mg/mL, 100 mg/mL injection
Blocks postsynaptic dopamine (D2) receptors in the limbic system of the brain. Decrease in dopamine neurotransmission has
been correlated with its antipsychotic effects, and its higher instance of extrapyramidal effects.
Decreases psychotic manifestations and exerts strong antiemetic effect.
Management of manifestations of psychotic disorders and for control of tics and vocal utterances of Gilles de la Tourette's
syndrome; for treatment of agitated states in acute and chronic psychoses. Used for short-term treatment of hyperactive
children and for severe behavior problems in children of combative, explosive hyperexcitability.
Cancer chemotherapy as an antiemetic in doses smaller than those required for antipsychotic effects; treatment of autism;
alcohol dependence; chorea.
Parkinson's disease, parkinsonism, seizure disorders, coma; alcoholism; severe mental depression, CNS depression; pregnancy
(category C), lactation. Safe use in children <3 y is not established.
Older adult or debilitated patients, urinary retention, glaucoma, severe cardiovascular disorders; thyrotoxicosis; patients
receiving anticonvulsant, anticoagulant, or lithium therapy.
Route & Dosage
Adult: PO 0.25 mg b.i.d. or t.i.d. IM 25 mg repeated q4h prn; Decanoate: 50100 mg q4wk
Child: PO 0.5 mg/d in 23 divided doses, may be increased by 0.5 mg q57d to 0.050.15 mg/kg/d
Adult: PO 35 mg b.i.d. or t.i.d., may need up to 100 mg/d IM 25 mg, may repeat q.h. prn; Decanoate: 50100 mg q4wk
Child: PO 0.050.15 mg/kg/d in 23 divided doses
Geriatric: PO 0.250.5 mg 12 times daily, may increase every 47 d (max: 4 mg/d in 23 divided doses)
Adult: PO 0.25 mg b.i.d. or t.i.d.
Child: PO 0.050.075 mg/kg/d in 23 divided doses
- Give with a full glass (240 mL) of water or with food or milk.
- Taper dosing regimen when discontinuing therapy. Abrupt termination can initiate extrapyramidal symptoms.
- Give by deep injection into a large muscle. Do not exceed 3 mL per injection site.
- Have patient recumbent at time of parenteral administration and for about 1 h after injection. Assess for orthostatic hypotension.
- Store in light-resistant container at 15°30° C (59°86° F), unless otherwise specified by manufacturer.
Discard darkened solutions.
Adverse Effects (≥1%)CNS: Extrapyramidal reactions:
Parkinsonian symptoms, dystonia, akathisia, tardive dyskinesia
(after long-term use); insomnia
, restlessness, anxiety, euphoria, agitation, drowsiness, mental depression
, lethargy, fatigue
weakness, tremor, ataxia, headache, confusion, vertigo; neuroleptic malignant syndrome,
hyperthermia, grand mal seizures, exacerbation of psychotic symptoms. CV:
Tachycardia, ECG changes, hypotension, hypertension (with overdosage). Endocrine:
Menstrual irregularities, galactorrhea, lactation, gynecomastia, impotence, increased libido, hyponatremia, hyperglycemia,
. Special Senses:
Blurred vision. Hematologic:
Mild transient leukopenia, agranulocytosis
Dry mouth, anorexia, nausea, vomiting, constipation
, diarrhea, hypersalivation. Urogenital:
Urinary retention, priapism. Respiratory: Laryngospasm,
bronchospasm, increased depth of respiration, bronchopneumonia, respiratory depression. Skin:
Diaphoresis, maculopapular and acneiform rash, photosensitivity. Other:
, variations in liver function tests, decreased serum cholesterol.
InteractionsDrug: cns depressants
depression; may antagonize activity of oral anticoagulants
may increase intraocular pressure; methyldopa
may precipitate dementia.
Well absorbed from GI tract; 60% reaches systemic circulation. Onset:
3045 min IM. Peak:
26 h PO; 1020 min IM; 67 d decanoate. Distribution:
Distributes mainly to liver with lower concentration in brain, lung, kidney, spleen, heart. Metabolism:
In liver. Elimination:
40% excreted in urine within 5 d; 15% eliminated in feces; excreted in breast milk. Half-Life:
Assessment & Drug Effects
- Monitor for therapeutic effectiveness. Because of long half-life, therapeutic effects are slow to develop in early therapy
or when established dosing regimen is changed. "Therapeutic window" effect (point at which increased dose or concentration
actually decreases therapeutic response) may occur after long period of high doses. Close observation is imperative when
doses are changed.
- Target symptoms expected to decrease with successful haloperidol treatment include hallucinations, insomnia, hostility, agitation,
- Monitor patient's mental status daily.
- Monitor for neuroleptic malignant syndrome (NMS) (see Appendix F), especially in those with hypertension or taking lithium.
Symptoms of NMS can appear suddenly after initiation of therapy or after months or years of taking neuroleptic (antipsychotic)
medication. Immediately discontinue drug if NMS suspected.
- Monitor for parkinsonism and tardive dyskinesia (see Appendix F). Risk of tardive dyskinesia appears to be greater in women
receiving high doses and in older adults. It can occur after long-term therapy and even after therapy is discontinued.
- Monitor for extrapyramidal (neuromuscular) reactions that occur frequently during first few days of treatment. Symptoms are
usually dose related and are controlled by dosage reduction or concomitant administration of antiparkinson drugs.
- Be alert for behavioral changes in patients who are concurrently receiving antiparkinson drugs.
- Monitor for exacerbation of seizure activity.
- Observe patients closely for rapid mood shift to depression when haloperidol is used to control mania or cyclic disorders.
Depression may represent a drug adverse effect or reversion from a manic state.
- Lab tests: Monitor WBC count with differential and liver function in patients on prolonged therapy.
Patient & Family Education
- Avoid use of alcohol during therapy.
- Do not drive or engage in other potentially hazardous activities until response to drug is known.
- Discuss oral hygiene with health care provider; dry mouth may promote dental problems. Drink adequate fluids.
- Avoid overexposure to sun or sunlamp and use a sunscreen; drug can cause a photosensitivity reaction.