Drug Interactions
Your healthcare professionals (e.g., doctor or pharmacist) may already be aware of any possible drug interactions and may be monitoring you for it. Do not start, stop or change the dosage of any medicine before checking with them first. This drug should not be used with the following medications because very serious interactions may occur: cabergoline, pergolide, sibutramine. Many drugs besides haloperidol may affect the heart rhythm (QT prolongation), including amiodarone, dofetilide, pimozide, quinidine, sotalol, procainamide, and macrolide antibiotics (such as erythromycin), among others. Therefore, before using haloperidol, report all medications you are currently using to your doctor or pharmacist. If you are currently using any of these medications listed above, tell your doctor or pharmacist before starting haloperidol. Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: anticholinergic medications (e.g., antispasmodics such as belladonna alkaloids, scopolamine), "blood thinners" (e.g., anticoagulants such as warfarin and heparin), carbamazepine, lithium, methyldopa, drugs for Parkinson's disease (e.g., levodopa and carbidopa, selegiline), quinupristin-dalfopristin, rifampin. Also report the use of drugs which might increase seizure risk (decrease seizure threshold) when combined with haloperidol such as: bupropion, isoniazid (INH), phenothiazines (e.g., chlorpromazine, fluphenazine, thioridazine), theophylline, tramadol, or tricyclic antidepressants (e.g., amitriptyline, nortriptyline), among others. Consult your pharmacist or doctor for more information. Tell your doctor of 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. This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.