Xenazine (Tetrabenazine)

How does it work?

Tetrabenazine works by depleting the stores of certain chemicals called neurotransmitters within nerve cells in the brain. These neurotransmitters include dopamine, serotonin and noradrenaline and are normally involved with the passage of messages between nerve cells in the brain and the normal functioning of the brain and nervous system.Depleting the brain of these neurotransmitters can help control movement disorders caused by diseases of the brain and nervous system, although the exact mechanism of action is not fully understood. Tetrabenazine is mainly used to control movement disorders associated with diseases of the brain and nervous system, such as Huntington's chorea, but can also be used to control movement disorders caused by antipsychotic medicines. The older antipsychotic medicines such as chlorpromazine, haloperidol and flupentixol can cause side effects involving involuntary movement of the tongue, face, mouth and jaw, which may sometimes be accompanied by involuntary movements of the arms and legs (tardive dyskinesia). If this is disabling or socially embarrasing, and persists despite stopping or reducing the dose of the antipsychotic, the symptoms can be treated using tetrabenazine. Tetrabenazine can also be used if it is not possible to stop or change the antipsychotic.

What is it used for?

  • Movement disorders associated with disease of the brain and spinal cord
  • Nerve cell breakdown resulting in irregular involuntary movements and brain disease (Huntington's chorea)
  • 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)

Warning!

  • Do not drink alcohol whilst taking this medicine.
  • This medicine may cause drowsiness. If affected do not drive or operate machinery.

Not to be used in

  • No known conditions

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.

  • There is no information about the safety of this medicine during pregnancy, but it has been widely used for many years without apparent ill consequence.
  • As there is no safety information available, the manufacturer does not recommend the use of this medicine when breastfeeding. Alternatively, if this medicine must be used, the mother should not breastfeed. Seek medical advice from your doctor.

Label warnings

  • This medication may cause drowsiness. If affected do not drive or operate machinery. Avoid alcoholic drink.

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. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.

  • Depression
  • Drowsiness
  • Disturbances of the gut such as diarrhoea, constipation, nausea, vomiting or abdominal pain
  • Low blood pressure (hypotension)
  • 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.

The side effects listed above may not include all of the side effects reported by the drug'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?

Tetrabenazine should not be taken at the same time as, or for 14 days following a course of monoamine oxidase inhibitor (MAOI) antidepressants, as this can cause restlessness, disorientation and confusion. Tetrabenazine opposes the effects of levodopa.Tetrabenazine should not be taken with alcohol as this may increase the drowsiness experienced.

Other medicines containing the same active ingredients

Tetrabenazine