Common questions about haloperidol - Brand names: Haldol, Serenace

Haloperidol belongs to a group of medicines called antipsychotics.

It's not clear how it works, but we do know it blocks certain nerve (neuron) activity in the brain. Haloperidol blocks a few different types of neuron activity. This is why it's used for several different conditions, and also why the side effects can vary so much between people.

Blocking neuron activity helps with anxiety and mental health conditions in some people. For example, it can help to stop delusions (when you think things that are not true) and hallucinations (when you see or hear things that are not there).

Haloperidol also helps block activity in the area of the brain that controls nausea and vomiting, which can help stop you feeling sick.

Haloperidol tablets and liquid usually work within 1 to 2 hours. The injections work more quickly, in around 20 to 40 minutes.

If you're taking haloperidol for a long-term mental health condition such as schizophrenia, it may take several weeks to feel the full benefit.

Haloperidol is good at treating short episodes of anxiety and agitation.

In some people, it's good at treating some mental health conditions and feeling or being sick (nausea and vomiting).

However, these conditions are sometimes hard to treat, and it's normal to need other medicines as well as, or instead of, haloperidol. It's also normal for your dose to be changed regularly to make it work best for you.

Haloperidol is safe to take for a long time. However, as with any medicine, if you take it for a long time there's more chance of getting side effects.

Some people taking haloperidol for a long time get a movement disorder called tardive dyskinesia, which causes rhythmic movements of your tongue, face, mouth or jaw. Talk to your doctor if you get these symptoms.

Haloperidol can cause sleepiness in some people. Although this is a side effect, getting more sleep can sometimes help with your condition.

If you notice any other side effects after taking haloperidol for a long time, talk to your doctor or pharmacist.

Some people find that they either put on or lose weight while taking haloperidol.

It's difficult to say whether your weight will change, but if it does and this is a problem for you, or you lose or gain a lot of weight, talk to your doctor.

It's important you do not suddenly stop taking haloperidol, unless a healthcare professional tells you to.

Suddenly stopping haloperidol can cause withdrawal effects, including feeling or being sick and having difficulty sleeping (insomnia).

It's usually best to reduce your dose gradually, especially if you've been taking it for a long time.

Sometimes, stopping haloperidol can cause the original symptoms to come back. This can happen weeks or months after you finish a course. If this happens, talk to your doctor.

Haloperidol is as effective as other antipsychotic medicines for short episodes of delirium and agitation, and for treating mental health conditions such as schizophrenia and bipolar disorder when they first start.

For some conditions like dementia, other antipsychotic medicines like risperidone may be better. However, haloperidol may still be the most suitable medicine for you and your symptoms.

Side effects can be more common with haloperidol than with other antipsychotic medicines like risperidone. Not everyone gets the same side effects and the risk of side effects also depends on what other medicines you're taking, and any other health conditions you have.

If you feel haloperidol is not working well enough or you have problems with side effects, talk to your doctor to see if another medicine would be better for you.

Haloperidol will not stop any type of contraception from working, including the combined pill and emergency contraception.

Haloperidol makes some people feel drowsy or dizzy. If this happens to you, do not drive or ride a bike until you feel better.

These side effects may improve with time if you're taking a longer course of haloperidol.

It's an offence to drive a car if your ability to drive safely is affected. It's your responsibility to decide if it's safe to drive. If you're in any doubt, do not drive.

Talk to your doctor or pharmacist if you're unsure whether it's safe for you to drive while taking haloperidol. GOV.UK has more information on the law on drugs and driving.

It's best to avoid alcohol while taking haloperidol.

Alcohol and haloperidol can both cause low blood pressure (hypotension) and make you feel drowsy or tired.

Apart from avoiding alcohol, you can eat and drink normally while taking haloperidol.

It's best to avoid smoking while taking haloperidol, as tobacco may make the medicine work less well.

Tell your doctor if you start or stop smoking, or if you suddenly change the amount you smoke, while taking haloperidol. Your dose may need to be changed.