Haloperidol
Brand names Dozic, Haldol, Serenace
Used in the following combined preparations None
GENERAL INFORMATION
Introduced in the 1960s, haloperidol is the most widely used of the group of drugs known as butyrophenones. It is effective in reducing the violent, aggressive manifestations of mental illnesses such as schizophrenia, mania, dementia, and other disorders in which hallucinations are experienced. This drug is also used for the short-term management of severe anxiety. It does not cure the underlying disorder, but it
does relieve the distressing symptoms. Haloperidol is also used in the control of Tourette’s syndrome and may be of benefit in children who have severe behavioural problems for which other drugs are ineffective.
The main drawback to the use of haloperidol is that it produces disturbing side effects – in particular, abnormal, involuntary movements and stiffness of the face and limbs.
QUICK REFERENCE
Drug group Butyrophenone antipsychotic drug
Overdose danger rating Medium
Dependence rating Low
Prescription needed Yes
Available as generic Yes
INFORMATION FOR USERS
Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.
How taken
Tablets, capsules, liquid, injection, depot injection.
Frequency and timing of doses
2-4 x daily.
Adult dosage range
Mental illness 1.5-20mg daily initially. Increased gradually, if necessary, up to a maximum of 200mg daily. Severe anxiety 1 mg daily.
Onset of effect
2-3 hours (by mouth); 20-30 minutes (by injection).
Duration of action
6-24 hours (by mouth). Up to 4 weeks (depot injection).
Diet advice
None.
Storage
Keep in a closed container in a cool, dry place out of the reach of children.
Missed dose
Take as soon as you remember. If your next dose is due within 3 hours, take a single dose now and skip the next.
Stopping the drug
Do not stop the drug without consulting your doctor; symptoms may recur.
Exceeding the dose
An occasional unintentional extra dose is unlikely to cause problems. Larger overdoses may cause unusual drowsiness, muscle weakness or rigidity, and/or faintness. Notify your doctor.
POSSIBLE ADVERSE EFFECTS
Haloperidol can cause a variety of minor anticholinergic symptoms that often become less marked with time. The most significant
adverse effect, abnormal movements of the face and limbs (parkinsonism), may be controlled by dosage adjustment.
INTERACTIONS
Sedatives
All drugs that have a sedative effect are likely to increase the sedative properties of haloperidol.
Antihistamines
Astemizole and terfenadine may have adverse effects on the heart if taken with haloperidol.
Anticholinergic drugs
The side effects of drugs with anticholinergic properties may be increased by haloperidol.
Anticonvulsant drugs
Dosage may need adjustment.
SPECIAL PRECAUTIONS
Be sure to tell your doctor if:
You have long-term liver or kidney problems.
You have heart or circulation problems.
You have had epileptic fits.
You have an overactive thyroid gland.
You have Parkinson’s disease. T You have had glaucoma.
You have asthma, bronchitis, or another lung disorder.
You are taking other medications.
Pregnancy
Safety in pregnancy not established. Discuss with your doctor.
Breast-feeding
The drug passes into the breast milk and may affect the baby. Discuss with your doctor.
Infants and children
Rarely required. Reduced dose necessary.
Over 60
Reduced dose may be necessary.
Driving and hazardous work
Avoid such activities until you have learned how haloperidol affects you because the drug may cause drowsiness and slowed reactions.
Alcohol
Avoid. Alcohol may increase the sedative effect of this drug.
PROLONGED USE
Use of this drug for more than a few months may lead to tardive dyskinesia (abnormal, involuntary movements of the eyes, face, and tongue). Occasionally, jaundice may occur.
