Pizotifen is a medicine used in the prevention of recurrent migraines and other vascular headaches. Pizotifen is also available under the brand name, ie Sanomigran.

What is it used for?

  • Preventing recurrent migraines.
  • Preventing cluster headaches and other vascular headaches.

How does it work?

  • Pizotifen is a medicine used in the prevention of recurrent migraines and other vascular headaches.
  • Although the cause of migraine attacks is not fully understood, it is thought that widening of blood vessels in the brain causes the pain associated with migraine attacks.
  • It is also believed that a chemical called serotonin (also known as 5HT) is released in the brain at the beginning of an attack. Serotonin triggers the release of other chemicals that cause blood vessels in the brain to widen. Serotonin itself causes blood vessels in the brain to narrow.
  • Pizotifen blocks serotonin (or 5HT) receptors in the brain. Blocking these receptors stops blood vessels in the brain from dilating and contracting.
Pizotifen also blocks histamine receptors in the brain. Histamine is responsible for causing inflammation and widening of blood vessels. Blocking the action of histamine prevents inflammation and stops the blood vessels from widening.
  • By stopping these changes to the blood vessels in the brain, pizotifen helps to prevent migraines from occuring. It is taken on a regular basis to reduce the number and severity of attacks of migraine and other types of vascular headache, such as cluster headaches. However, the medicine won't stop an attack once it has started.
  • How do I take it?

    • This medicine should be taken regularly every day to help prevent your headaches. It should not be taken to treat a headache, as it will not stop a migraine once it has started.
    • Follow the instructions given by your doctor regarding how many tablets to take and how often to take them. This will vary from person to person. The instructions should be printed on the dispensing label that your pharmacist has put on the packet of medicine. If you are not sure about anything you should ask your doctor or pharmacist for advice.
    • Pizotifen can be taken as a single dose at bedtime, or as three doses spread over the day. Follow the instructions given by your doctor.
    • Pizotifen tablets can be taken either with or without food.
    • If you forget to take a dose, take it as soon as you remember, unless it is nearly time for your next dose. In this case, leave out the missed dose and take your next dose as usual when it is due. Do not take a double dose to make up for a missed dose.
    • You should not stop taking this medicine suddenly unless directed by your doctor, as this is likely to make your migraines come back or get worse. It may also cause withdrawal symptoms such as anxiety, tremors, difficulty sleeping and nausea. When you stop treatment it is recommended that this is done gradually. Follow the instructions given by your doctor.

    Use with caution in

    • People with decreased kidney or liver function.
    • People who have difficulty passing urine (urinary retention), for example men with an enlarged prostate gland.
    • People with closed angle glaucoma.
    • People with a history of epilepsy.

    Not to be used in

    • Children under five years of age.
    • Pizotifen tablets contain lactose and should not be taken by people with rare hereditary problems of galactose intolerance, severe lactase deficiency or glucose-glactose malabsorption.
    • 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 for use during pregnancy has not been established. It is not recommended for use in pregnancy unless considered essential by your doctor. Seek further medical advice from your doctor.
    • This medicine may pass into breast milk in small amounts. The manufacturer states that it is not recommended for mothers who are breastfeeding. 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.

    Very common (affect more than 1 in 10 people)

    • Increased appetite.
    • Weight gain.

    Common (affect between 1 and 10 out of every 100 people)

    • Sleepiness or drowsiness.
    • Fatigue.
    • Dizziness.
    • Feeling sick.
    • Dry mouth.

    Uncommon (affect between 1 and 10 out of every 1000 people)

    • Constipation.

    Rare (affect between 1 and 10 out of every 10,000 people)

    • Depression.
    • Anxiety.
    • Agitation.
    • Aggression.
    • Hallucinations.
    • Difficulty sleeping (insomnia).
    • Pins and needles sensations.
    • Pain in the muscles or joints.
    • Rashes.
    • Swelling of the face.

    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 make sure that the combination is safe.

    There is an increased risk of feeling drowsy or sleepy if you take any of the following in combination with pizotifen:

    • alcohol
    • antipsychotics, eg haloperidol, chlorpromazine
    • baclofen
    • barbiturates, eg phenobarbital, amobarbital
    • benzodiazepines, eg diazepam, temazepam
    • sedating antihistamines, eg chlorphenamine, hydroxyzine, promethazine
    • sleeping tablets, eg zopiclone
    • strong opioid painkillers, eg codeine, morphine, tramadol, fentanyl
    • tricyclic antidepressants, eg amitriptyline.
    • Pizotifen may oppose the blood pressure lowering effect of guanethidine.