Before taking haloperidol, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems.
Before using this medicine, consult your doctor or pharmacist if you have: a certain severe nervous system problem (severe CNS depression), Parkinson’s disease.
Before using this medication, tell your doctor or pharmacist your medical history, especially of:
- bipolar disorder
- difficulty urinating (e.g., due to prostate problems)
- heart problems (e.g., angina)
- overactive thyroid (hyperthyroidism)
- low white blood cell count
Haloperidol may cause a condition that affects the heart rhythm (QT prolongation). The risk of QT prolongation may be increased if you have certain medical conditions or taking other drugs that may cause QT prolongation. Before using haloperidol, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).
This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
Before having surgery, be sure to tell your doctor or dentist that you are taking haloperidol.
This medication can reduce sweating, making you more likely to get heatstroke. Avoid hard work and exercise in hot weather.
Older adults may be more sensitive to the side effects of this drug, especially drowsiness, difficulty urinating, and heart effects such as QT prolongation (see above).
During pregnancy, this medication should be used only when clearly needed. Babies born to mothers who have used this drug during the last 3 months of pregnancy may infrequently develop symptoms including muscle stiffness or shakiness, drowsiness, feeding/breathing difficulties, or constant crying. If you notice any of these symptoms in your newborn especially during their first month, tell the doctor right away.
Since untreated mental/mood problems (such as schizophrenia, schizoaffective disorders) can be a serious condition, do not stop taking this medication unless directed by your doctor. If you are planning pregnancy, become pregnant, or think you may be pregnant, immediately discuss with your doctor the benefits and risks of using this medication during pregnancy.
This drug passes into breast milk and could have undesirable effects on a nursing infant. Consult your doctor before breast-feeding.
Some products that may interact with this drug include:
- anticholinergic medications (e.g., antispasmodics such as belladonna alkaloids, scopolamine)
- drugs for Parkinson’s disease (e.g., levodopa and carbidopa, selegiline)
Many drugs besides haloperidol may affect the heart rhythm (QT prolongation), including amiodarone, dofetilide, pimozide, quinidine, sotalol, procainamide, macrolide antibiotics (such as erythromycin), among others. Therefore, before using haloperidol, report all medications you are currently using to your doctor or pharmacist.
Also report the use of drugs which might increase seizure risk (decrease seizure threshold) when combined with haloperidol such as:
- isoniazid (INH)
- phenothiazines (e.g., chlorpromazine, fluphenazine, thioridazine)
- tricyclic antidepressants (e.g., amitriptyline, nortriptyline)
Consult your pharmacist or doctor for more information.
Tell your doctor or pharmacist if you also take drugs that cause drowsiness such as:
- certain antihistamines (e.g., diphenhydramine)
- anti-seizure medications (e.g., phenytoin, valproic acid)
- medicine for sleep or anxiety (alprazolam, clonazepam, zolpidem)
- muscle relaxants
- narcotic pain relievers (e.g., codeine)
- psychiatric medications (e.g., risperidone, trazodone).
Check the labels on all your medicines (e.g., allergy, cough-and-cold products) because they may contain drowsiness-causing ingredients. Ask your pharmacist about the safe use of those products.