This information should not be used to decide whether or not to take Haldol or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Haldol. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.
The selected site is cleansed with an antimicrobial and is allowed to dry. It is injected with the dominant hand using a quick, darting motion perpendicular to the patient's body at an angle between 72 and 90 degrees, as a faster injection is less painful. The needle is then stabilized with the nondominant hand while the dominant hand slides to the plunger to slowly instill the medication, as a rapid injection causes more discomfort. The CDC does not recommend the outdated practice of aspirating for blood to rule out injecting into a blood vessel. The needle is withdrawn at the same angle inserted. Using the "Z track" or zigzag technique is recommended, where the skin is pulled and held down to one side with the nondominant hand about an inch and after the needle is withdrawn the displaced skin is allowed to return to its normal position. This is to ensure that the medication does not leak back along the needle track. Gentle pressure is applied with a gauze but the site is not massaged to prevent forcing the medication into subcutaneous tissue. 
Cardiovascular: Tachycardia, hypertension and ECG changes including ventricular arrhythmias and/or prolongation of the QT interval and ECG pattern changes compatible with the polymorphous configurations of torsades de pointes have been reported. Hypotension has occurred, but severe orthostatic hypotension has not been reported. However, should it occur, supportive measures, including . vasopressors, such as norepinephrine, may be required. Epinephrine should not be used; since haloperidol decanoate may block the vasoconstrictor effects of this drug.