Other permanent side effects are similar to many other typical antipsychotics, namely extrapyramidal symptoms as a result of dopamine blockade in subcortical areas of the brain. This may result in symptoms similar to those seen in Parkinson's disease and include a restlessness and inability to sit still known as akathisia , a slow tremor and stiffness of the limbs.  Zuclopenthixol is thought to be more sedating than the related flupentixol , though possibly less likely to induce extrapyramidal symptoms than other typical depots.  As with other dopamine antagonists, zuclopenthixol may sometimes elevate prolactin levels; this may occasionally result in amenorrhoea or galactorrhoea in severe cases. Neuroleptic malignant syndrome is a rare but potentially fatal side effect. Any unexpected deterioration in mental state with confusion and muscle stiffness should be seen by a physician.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Some products that may interact with this drug include: anticholinergic medications (., antispasmodics such as belladonna alkaloids, scopolamine), alpha blockers (., doxazosin, prazosin, terazosin), dopamine agonists (., cabergoline, pergolide), metoclopramide, piperazine, drugs for Parkinson's disease (., levodopa and carbidopa, selegiline), certain drugs for high blood pressure (methyldopa, guanethidine, guanadrel, hydralazine). Many drugs besides zuclopenthixol may affect the heart rhythm (QT prolongation), including amiodarone, dofetilide, pimozide, procainamide, quinidine, sotalol, macrolide antibiotics (such as erythromycin), among others. Therefore, before using zuclopenthixol, report all medications you are currently using to your doctor or pharmacist. Tell your doctor or pharmacist if you are taking other products that cause drowsiness such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine). Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.