haloperidol decanoate at a glance
Medicine class
Long-acting butyrophenone antipsychotic.
Administration
A healthcare professional injects it deep into a gluteal muscle. It must never be injected into a vein.
Important ingredients
Contains sesame oil and benzyl alcohol, which can cause allergic reactions.
What is haloperidol decanoate used for?
Licensed uses are:
Maintenance treatment of schizophrenia in adults already stabilised with oral haloperidol.
Maintenance treatment of schizoaffective disorder in adults already stabilised with oral haloperidol.
How does haloperidol decanoate work?
The depot ester is released slowly from muscle and converted to active haloperidol. Haloperidol blocks dopamine D2 receptors, which can reduce hallucinations and delusions. This action also explains movement disorders and raised prolactin.
haloperidol decanoate preparations and strengths
Injection
Route: Parenteral
Strengths: 50 mg/mL, 100 mg/mL
How to take haloperidol decanoate
A doctor or nurse gives it as a deep injection into a gluteal muscle, alternating sides where appropriate. It is for intramuscular use only and must never be given intravenously.
Tell the clinical team about allergies, particularly sesame allergy.
Do not drive or operate machinery until you know whether it causes sleepiness or reduced alertness.
Alcohol can increase sleepiness and impaired alertness.
haloperidol decanoate side effects
Common or expected effects
- Movement problems such as tremor, stiffness, restlessness or parkinsonism
- Sleepiness or sedation
- Difficulty sleeping or depression
- Constipation, dry mouth or increased saliva
- Sexual problems
- Weight gain
- Injection-site pain, irritation or reaction
Get urgent medical advice
- High fever, severe muscle stiffness, confusion or reduced consciousness
- New or persistent uncontrolled movements
- Fainting or a fast or irregular heartbeat
- Severe allergic reaction
- A painful swollen leg, sudden chest pain or breathlessness
- Seizures, severe swallowing difficulty or marked muscle-breakdown symptoms
haloperidol decanoate in pregnancy
The product information says it is preferable to avoid haloperidol decanoate during pregnancy as a precaution. Haloperidol may be used when recommended by a specialist. Exposure near delivery can cause temporary movement, feeding, breathing or withdrawal symptoms in the newborn. Discuss pregnancy or plans for pregnancy promptly with mental-health and maternity teams.
haloperidol decanoate while breastfeeding
Haloperidol enters breast milk. Evidence specific to the long-acting injection is limited, so seek specialist advice. If breastfeeding, monitor the infant for unusual sleepiness, poor feeding, abnormal movements or inadequate weight gain.
haloperidol decanoate interactions
Check all prescribed, non-prescribed and herbal products before treatment. Important examples include:
Medicines that prolong the QT interval
Examples include amiodarone, sotalol, citalopram, escitalopram, some macrolide or quinolone antibiotics and methadone. They can increase dangerous heart-rhythm risk and are contraindicated with this product.
CYP3A4 or CYP2D6 inhibitors
Fluoxetine, paroxetine, ritonavir, itraconazole and verapamil can raise haloperidol concentrations and adverse-effect risk.
Enzyme inducers
Carbamazepine, phenytoin, phenobarbital, rifampicin and St John’s wort can lower haloperidol concentrations and reduce effectiveness.
Common questions about haloperidol decanoate
Answers are fully visible for fast scanning and source review.
Why is oral haloperidol used first?
Previous oral treatment establishes response and reduces the chance of discovering an unexpected sensitivity after a long-acting injection.
Can it cause movement problems?
Yes. Restlessness, tremor, stiffness, slowed movement, muscle spasms and persistent involuntary movements can occur and should be reported promptly.
Can it affect the heart?
It can prolong the QT interval and rarely cause serious abnormal rhythms. Cardiac history, interacting medicines, ECG findings and electrolytes are important.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.