Fluanxol (Flupentixol)

How does it work?

Fluanxol tablets contain the active ingredient flupentixol (previously spelt flupenthixol in the UK), which is a type of medicine called an antipsychotic.

In high doses, flupentixol is used to treat schizophrenia and other psychotic illnesses (see the Depixol factsheets linked at the end of this page for more information about this use of flupentixol). Fluanxol tablets contain a lower dose of flupentixol and are used to treat depression.

It is not fully understood how low doses of flupentixol work in treating depression, but its mechanism of action is not the same as that of other antidepressants.

Flupentixol is thought to work by affecting the activity of a natural compound called dopamine in the brain. Dopamine is known as a neurotransmitter, and is involved in transmitting messages between brain cells. It is known to be involved in regulating mood and behaviour, amongst other things.

Unlike other antidepressants, flupentixol usually starts to produce an antidepressant effect within two to three days. However, it may not make you feel fully better for at least few weeks.

What is it used for?

  • Depression, with or without anxiety.

How do I take it?

  • The dose of this medicine that is prescribed and how often to take the tablets will vary from person to person. It is important to follow the instructions given by your doctor. These will also be printed on the dispensing label that your pharmacist has put on the medicine.
  • Fluanxol tablets should usually be taken in the morning. However, if you are taking a daily dose higher than 2mg, this should be split into separate doses. Your last dose should not be taken any later than 4pm, as this may stop you sleeping properly.
  • The tablets can be taken either with or without food.
  • If you forget to take a dose don't worry, just take your next dose as normal. Don't take a double dose to make up for a missed dose.
  • You should not suddenly stop taking this medicine unless your doctor tells you otherwise, as this may cause withdrawal symptoms such as nausea, vomiting, diarrhoea, sweating, pins and needles sensations, difficulty sleeping, restlessness, anxiety or tremor. Withdrawal symptoms are temporary and are not due to addiction or dependence on the medicine. They can usually be avoided by stopping the medicine gradually. Follow the instructions given by your doctor when it is time to stop treatment with this medicine.


  • This medicine may cause drowsiness and blurred vision. If affected do not drive or operate machinery. You should avoid drinking alcohol while taking this medicine because it can make drowsiness worse.
  • Although it can cause drowsiness, this medicine can also have an alerting effect, so you should avoid taking it in the evening because it may cause you problems sleeping.
  • Depression and other psychiatric illnesses are associated with an increased risk of suicide, self-harm, and thoughts about harming or killing yourself. You should be aware that although this medicine may start to work in two to three days, it may not make you feel fully better for at least few weeks. It is important that you keep taking it in order for it to work properly and for you to feel better. If you feel your depression or anxiety has got worse, or if you have any distressing thoughts, or feelings about suicide or harming yourself in the first few weeks of treatment, or indeed at any point during treatment or after stopping treatment, then it is very important to talk to your doctor.
  • Antipsychotic medicines are associated with an increased risk of getting a blood clot in a vein (deep vein thrombosis) or in the lungs (pulmonary embolism). For this reason, you should consult a doctor immediately if you get any of the following symptoms, which could suggest you have a blood clot: stabbing pains and/or unusual redness or swelling in one leg, pain on breathing or coughing, coughing up blood or sudden breathlessness.
  • If you experience any abnormal movements of your hands, legs, face, neck or tongue while taking this medicine, for example tremor, twitching or rigidity, you should let your doctor know as your treatment may need to be stopped.
  • Consult your doctor immediately if you experience the following symptoms while taking this medicine: high fever, sweating, muscle stiffness, faster breathing and drowsiness or sleepiness. These symptoms may be due to a rare side effect known as the neuroleptic malignant syndrome, and if so your treatment should be stopped.

Use with caution in

  • Elderly people.
  • Young adults.
  • People with a history of suicidal behaviour or thoughts.
  • Decreased liver function or liver disease.
  • Kidney failure.
  • Severe disease affecting the lungs or airways.
  • Heart disease, such as heart failure, recent heart attack, very slow heart rate (bradycardia) or irregular heart beats (arrhythmias).
  • People with a personal or family history of a type of abnormal heart rhythm, seen on a heart monitoring trace (ECG) as a 'prolonged QT interval'.
  • People with disturbances in the normal levels of salts (electrolytes) in their blood, for example low magnesium or potassium levels.
  • Elderly people with dementia. (Antipsychotic medicines have been shown to increase the risk of stroke and death in this group of patients. Flupentixol is not licensed or recommended for treating behavioural disturbances in elderly people with dementia).
  • People with risk factors for having a stroke, for example a history of stroke or mini-stroke (TIA), smoking, diabetes, high blood pressure, or a type of irregular heartbeat called atrial fibrillation.
  • People with a personal or family history of blood clots (venous thromboembolism), for example in a vein of the leg (deep vein thrombosis) or in the lungs (pulmonary embolism).
  • People with other risk factors for getting a blood clot, for example smoking, being overweight, taking the contraceptive pill, being over 40, recent major surgery or being immobile for prolonged periods.
  • Diabetes. People with diabetes should monitor their blood sugar levels more closely whilst taking this medicine. This medicine may increase the blood sugar levels in the body.
  • Epilepsy.
  • People with conditions that increase the risk of convulsions, eg brain damage or withdrawal from alcohol.
  • Parkinson's disease.
  • Abnormal muscle weakness (myasthenia gravis).
  • Closed angle glaucoma.
  • Men with an enlarged prostate gland (prostatic hypertrophy).
  • People with a tumour of the adrenal gland (phaeochromocytoma).
  • People with an underactive or overactive thyroid gland.
  • Hereditary blood disorders called porphyrias.
  • People who are allergic to other similar antipsychotic medicines, eg zuclopenthixol.

Not to be used in

  • Severe depression requiring electroconvulsive therapy (ECT) or admission to hospital.
  • States of excitement, agitation or overactivity, including mania.
  • People in unresponsive, unconscious states (comatose states).
  • People with reduced awareness, slow reactions or extreme drowsiness, for example due to drugs, medicines or illness that reduce activity in the central nervous system.
  • People with a serious problem with the blood circulatory system (circulatory collapse).
  • Rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption (Fluanxol tablets contain lactose).
  • Rare hereditary problems of fructose intolerance, glucose-galactose malabsorption or sucrase-isomaltase insufficiency (Fluanxol tablets contain sucrose).
  • This medicine is not recommended for use in children and adolescents under 18 years of age.

This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.

If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.

Pregnancy and breastfeeding

Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

  • The safety of this medicine during pregnancy has not been established. It should not be used in pregnancy, particularly in the first and third trimesters, unless considered essential by your doctor. If the medicine is used during the third trimester it could cause side effects or withdrawal symptoms in the baby after birth and the baby may need extra monitoring because of this. Seek further medical advice from your doctor.
  • If you do get pregnant while taking this medicine it is important to consult your doctor straight away for advice. You should not suddenly stop taking this medicine unless your doctor tells you to, as this could cause withdrawal symptoms (see warning above).
  • This medicine passes into breast milk. As it could have harmful effects on a nursing infant the manufacturer recommends that mothers who need to take this medicine should not breastfeed and bottlefeed instead. Seek further medical advice from your doctor.

Side effects

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here does not mean that all people using this medicine will experience that or any side effect.

  • Abnormal movements of the hands, legs, face, neck and tongue, eg tremor, twitching, rigidity (extrapyramidal effects).
  • Anxiety, restlessness and agitation (akathisia).
  • Increased salivation or dry mouth.
  • Sleepiness.
  • Rhythmical involuntary movement of the tongue, face, mouth and jaw, which may sometimes be accompanied by involuntary movements of the arms and legs (tardive dyskinesia - see warning section above).
  • Increased heart rate (tachycardia), awareness of your heartbeat (palpitations) or an abnormal heart rhythm.
  • A drop in blood pressure (hypotension) that may cause dizziness.
  • Interference with the body's temperature regulation (this is more common in elderly people and may cause heat stroke in very hot weather or hypothermia in very cold weather).
  • Headache.
  • Changes in appetite and weight.
  • Problems with attention or speech.
  • Nervousness or agitation.
  • Difficulty sleeping (insomnia).
  • Visual disturbances such as blurred vision.
  • Disturbances of the gut such as constipation, diarrhoea, indigestion, wind, nausea and vomiting.
  • Difficulty passing urine.
  • Excessive sweating.
  • Skin reactions such as rashes, itching, increased sensitivity to sunlight.
  • Sexual problems, such as erectile dysfunction, change in sex drive or problems with orgasm.
  • Seizures (convulsions).
  • Increased blood glucose levels. Tell your doctor if you notice you feel unusually hungry or thirsty, or need to pass urine more often than usual. People with diabetes should monitor their blood sugar closely.
  • High blood prolactin (milk producing hormone) level (hyperprolactinaemia). Sometimes this can lead to symptoms such as breast enlargement, production of milk and stopping of menstrual periods.
  • High temperature combined with falling levels of consciousness, paleness, sweating and a fast heart beat (neuroleptic malignant syndrome). Requires stopping the medicine and immediate medical treatment - see warning section above.
  • Uncontrolled rolling of the eyes and neck (oculogyric crisis). Requires immediate treatment.
  • Decrease in the number of white blood cells or platelets in the blood (leucopenia or thrombocytopenia). Tell your doctor if you get unexplained bruising or bleeding, purple spots, sore throat, mouth ulcers, high temperature (fever), feeling tired or general illness while taking this medicine, as these symptoms could suggest a problem with your white blood cells. Your doctor may want you to have a blood test to check the numbers of blood cells in your blood.
  • Jaundice or liver problems (tell your doctor straight away if you notice any yellowing of your eyes or skin while taking this medicine).
  • Abnormal blood clot in the blood vessels (venous thromboembolism - see warning section above).

The side effects listed above may not include all of the side effects reported by the medicine's manufacturer.

For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

How can this medicine affect other medicines?

It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to ensure that the combination is safe.

There may be an increased risk of drowsiness and sedation if flupentixol is taken with any of the following (which can also cause drowsiness):

  • alcohol
  • barbiturates, eg amobarbital, phenobarbital
  • benzodiazepines, eg diazepam, temazepam
  • MAOI antidepressants, eg phenelzine
  • sedating antihistamines, eg chlorphenamine, hydroxyzine
  • sleeping tablets, eg zopiclone
  • strong opioid painkillers, eg morphine, codeine
  • tricyclic antidepressants, eg amitriptyline.

Flupentixol may enhance the blood pressure-lowering effects of medicines that lower blood pressure, including medicines used to treat high blood pressure (antihypertensives) and medicines that lower blood pressure as a side effect, eg benzodiazepines. If you are taking medicines that lower blood pressure you should tell your doctor if you feel dizzy or faint after starting treatment with this medicine, as your doses may need adjusting.

There may be an increased risk of side effects such as dry mouth, constipation, confusion or heat stroke (in hot and humid conditions) if other medicines that can have anticholinergic effects, such as the following, are taken in combination with flupentixol:

  • anticholinergic medicines for Parkinson's symptoms, eg procyclidine
  • antihistamines, eg brompheniramine, chlorphenamine
  • other antipsychotic medicines
  • antisickness medicines, eg promethazine, meclozine, cyclizine
  • antispasmodic medicines, eg hyoscine
  • MAOI antidepressants, eg phenelzine
  • medicines for urinary incontinence, eg oxybutynin, flavoxate, tolterodine, propiverine, trospium
  • muscle relaxants, eg baclofen
  • tricyclic antidepressants, eg amitriptyline.

Medicines that increase the risk of a type of abnormal heart rhythm, seen as a 'prolonged QT interval' on an ECG, should be avoided in combination with flupentixol. These medicines include the following:

  • antiarrhythmics (medicines to treat abnormal heart beats), eg amiodarone, procainamide, disopyramide, sotalol
  • the antihistamines astemizole, mizolastine or terfenadine
  • arsenic trioxide
  • atomoxetine
  • certain antidepressants, eg amitriptyline, imipramine, maprotiline
  • certain antimalarials, eg halofantrine, chloroquine, quinine, mefloquine, Riamet
  • certain antipsychotics, eg thioridazine, pimozide, sertindole , haloperidol
  • cisapride
  • dronedarone
  • droperidol
  • intravenous erythromycin or pentamidine
  • methadone
  • moxifloxacin
  • saquinavir.

There may also be an increased risk of a prolonged QT interval if medicines that can alter the levels of salts such as potassium or magnesium in the blood, eg diuretics such as furosemide, are taken in combination with flupentixol.

Flupentixol may reduce the blood pressure lowering effect of guanethidine.

There may be an increased risk of side effects such as tremor, movement disorders, confusion or drowsiness if flupentixol is taken in combination with lithium or sibutramine.

There may be an increased risk of movement disorders (extrapyramidal side effects) if flupentixol is taken in combination with metoclopramide.

Flupentixol may oppose the effect of anticonvulsant medicines used to treat epilepsy.

Flupentixol may increase blood sugar levels and disturb the control of diabetes. People with diabetes may need an adjustment in the dose of their antidiabetic medication.

Flupentixol may oppose the effects of dopamine agonists used to treat Parkinson's disease, eg levodopa, apomorphine, bromocriptine, cabergoline, pergolide, ropinirole, rotigotine.

Flupentixol may oppose the effect of histamine (used to treat leukaemia) and is not recommended for people having this treatment.

Other medicines containing the same active ingredient

Depixol injection Depixol tablets

NB. Depixol tablets and injection contain higher doses of flupentixol than Fluanxol and are not used to treat depression.