Antipsychotic drugs

Do they work?

We don't know. There hasn't been any good research on antipsychotic drugs as a treatment for people with anorexia. But we do know that they cause side effects, including heart problems. These can be very dangerous for people with anorexia.

What are they?

Antipsychotic drugs are usually used to treat mental health problems such as schizophrenia. People with schizophrenia have periods of time when they are out of contact with reality. They may hear things, often voices, that aren't really there, and they may have strange beliefs and feel very tense and jumpy. Doctors call this kind of illness psychosis. Medicines used to treat it help people feel much calmer.

Having anorexia is not the same as having psychosis. It's a very different kind of illness.

When these drugs have been used to treat anorexia, it's because they can have a calming effect. They are also used because one of their side effects is that people taking them tend to put on weight. And sometimes these drugs are given to people with anorexia who also had other serious mental health problems.[3]

Common antipsychotic drugs (with their brand names) include:

• chlorpromazine (Largactil)
• haloperidol (Haldol, Dozic, Serenace)
• pimozide (Orap).

How can they help?

There is no evidence that antipsychotic drugs can help people with anorexia to feel less anxious about eating or to put on weight.

Why should they work?

Antipsychotic drugs reduce the effects of a chemical in your brain called dopamine. Dopamine affects your thoughts and your emotions, and it helps control how your muscles move. Researchers don't really know why changing the level of dopamine might help ease feelings of fear, worry and agitation.[4] [5]

Can they be harmful?

There aren't any studies of antipsychotic drugs used to treat anorexia, so we don't know exactly what side effects you might get. But studies of people taking this drug for other mental health problems show some serious side effects. They include:[6]

• Sleepiness
• Dizziness
• A dry mouth
• Skin that is sensitive to the sun
• A twitching head and twitching neck and face muscles (Newer drugs such as olanzapine don't cause this side effect.)
• Problems with the electrical signals that help control your heart rate.

One study has found that haloperidol increases the risk of dangerous heart problems.[7] Haloperidol interferes with the electrical activity in the heart, making it beat too quickly. If this isn't treated, it can make the heart suddenly stop working (called sudden cardiac arrest). And if someone's heart stops working they may die.

In the study, the risk of heart problems was highest in women, elderly people and people who'd recently started taking haloperidol (they'd started taking it in the last 90 days).[7] But it's not clear exactly how big the risk is.[8] One study found that, on average, over a year, about 1 in 1,000 people die suddenly of cardiac arrest.[7] Haloperidol seems to increase this risk to roughly 5 in 1,000 deaths each year.

In the US, an organisation called the Food and Drug Administration (FDA) checks the safety of medicines. The FDA says at least 28 people taking unusually high doses of haloperidol, or having haloperidol injections into a vein instead of a muscle, have had problems with a fast heartbeat. Some people have died. The FDA advises doctors to take account of this risk when deciding on treatments.[8]

If your body is starving because of anorexia and your weight is low for your height, you may be at increased risk of these drugs affecting your heart.[9] [1] [10] [11] [2]

To learn more, see What you can expect from the NHS.

What's the evidence for antipsychotic drugs?