Effexor XR and Haldol

In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.

Venlafaxine can increase the blood levels of haloperidol. This may increase side effects such as drowsiness, depression, seizures, rapid heartbeat, low blood pressure, Parkinson-like symptoms, and abnormal muscle movements involving the face or limbs. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. In addition, combining venlafaxine and haloperidol can increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening, although it is a relatively rare side effect of either medication. You may be more susceptible if you have a heart condition called congenital long QT syndrome, other cardiac diseases, conduction abnormalities, or electrolyte disturbances (for example, magnesium or potassium loss due to severe or prolonged diarrhea or vomiting). Talk to your doctor if you have any questions or concerns. Your doctor may already be aware of the risks, but has determined that this is the best course of treatment for you and has taken appropriate precautions and is monitoring you closely for any potential complications. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with these medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

MONITOR CLOSELY: Haloperidol can cause dose-related prolongation of the QT interval. Theoretically, coadministration with other agents that can prolong the QT interval such as venlafaxine may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death. Haloperidol treatment alone has been associated with a number of reported cases of torsade de pointes and sudden death. The majority of cases involved intravenous administration or use of higher than recommended dosages. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia). In addition, the extent of drug-induced QT prolongation is dependent on the particular drugs involved and dosages of the drugs. Pharmacokinetically, venlafaxine has been shown to increase haloperidol serum concentrations by decreasing its clearance. In 24 healthy subjects, venlafaxine given at 75 mg every 12 hours to steady state reduced the clearance of a single oral 2 mg dose of haloperidol by 42%, resulting in increases of 88% and 70% in haloperidol peak plasma concentration (Cmax) and systemic exposure (AUC), respectively, with no change in elimination half-life. The mechanism of interaction is unknown.

MANAGEMENT: Caution is recommended if haloperidol is used in combination with other drugs that can prolong the QT interval, particularly when administered intravenously or at higher than recommended dosages. Dose adjustments for haloperidol may be required when used with venlafaxine due to potentially increased haloperidol levels. Patients should be monitored for increased adverse effects such as tachycardia, hypotension, extrapyramidal reactions (e.g., Parkinson-like symptoms, akathisia, dystonia), drowsiness, depression, and seizures. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope.

Effexor XR

Generic Name: venlafaxine

Brand name: Effexor XR, Effexor

Synonyms: n.a.

What is Effexor XR?

Haldol

Generic Name: haloperidol

Brand name: Haldol, Haldol Decanoate

Synonyms: n.a.

What is Haldol?