 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST]  for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: a certain severe nervous system problem (severe CNS depression), Parkinson's disease, bipolar disorder, difficulty urinating (such as due to prostate problems), glaucoma, heart problems (such as angina), overactive thyroid (hyperthyroidism), seizures, low white blood cell count. Haloperidol decanoate may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away. The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using haloperidol decanoate, 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). Low levels of potassium or magnesium in the blood may also increase </s>