Sumatriptan - for migraine and cluster headaches

About sumatriptan

Em pessoas com enxaqueca, it is thought that some chemicals in the brain increase in activity and as a result parts of the brain then send out confused signals which result in the symptoms of headache and sickness. Why people with migraine should develop these chemical changes is not clear. Many migraine attacks occur for no apparent reason, but for some people there may be things which trigger an attack, like certain foods or drinks.

Cefaleias em salvas consist of attacks of severe one-sided pain in the head. Typically, a number of attacks will occur over several weeks and then pass. It may then be weeks, months or years until the next cluster of headaches develops.

Sumatriptan belongs to a class of medicines known as 5HT₁-receptor agonists. They are also known simply as triptans. Triptans work by stimulating the receptors of a natural substance in the brain, called serotonin (or 5HT). This eases the symptoms of migraine and cluster headaches.

There are two strengths of sumatriptan tablet available (50 mg and 100 mg), one strength of injection (6 mg/0.5 ml) and one strength of nasal spray (10 mg/actuation). The injection is usually prescribed for people with cluster headaches, whereas the injection, spray or tablets may be prescribed for people with migraines.

Sumatriptan 50 mg tablets can be purchased from pharmacies for the treatment of migraine headache. The pharmacist will need to check that the medicine is suitable for you to take.

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking sumatriptan it is important that your doctor knows:

• If you are aged over 65 years or under 18 years.

• Se você está grávida ou amamentando.

• If you have a heart condition such as angina, or if you have had a heart attack.

• Se você tem pressão alta (hipertensão).

• If you have circulation problems.

• If you have any problems with the way your liver works or with the way your kidneys work.

• If you have ever had a stroke or a transient ischaemic attack (this is also referred to as a TIA, or 'mini-stroke').

• Se você já teve uma convulsão (ataque epiléptico).

• If you have ever had an allergic reaction to a medicine. It is particularly important that you tell your doctor if you have had a bad reaction to a sulfonamide antibiotic (such as co-trimoxazole or sulfadiazine).

• Se você estiver tomando ou usando qualquer outro medicamento. Isso inclui quaisquer medicamentos que você esteja tomando e que estejam disponíveis para compra sem receita médica, bem como medicamentos fitoterápicos e complementares.

• Before you start this treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about sumatriptan and a full list of the side-effects which you may experience from taking it. It will also provide you with a step-by-step guide and diagrams to show you how to use the preparation you have been supplied with. If you are still unsure what to do, ask your pharmacist for further advice.

• Your dose will be on the label of the pack. Take sumatriptan exactly as your doctor tells you to.

• If you are taking tablets: take one (50 mg or 100 mg) tablet with a drink of water, as soon as the headache phase develops. You can take Imigran Radis® tablets stirred into a small amount of water. If your migraine at first improves but then comes back, you may take a further dose, providing it is at least two hours after the initial dose. If the first tablet has no effect, do not try a second dose for the same attack, as it is unlikely to work.

• If you are using the injection: inject one dose as soon as the headache develops. If your headache at first improves but then comes back, you may use one further dose, providing it is at least one hour after the initial dose. Do not use more than two doses in 24 hours. If the first dose has no effect, do not try a second dose for the same attack, as it is unlikely to work. The needle shield may contain natural latex rubber.

• If you using the nasal spray: use the spray as soon as the headache phase develops. If your migraine at first improves but then comes back, you can use the spray again providing it is at least two hours after your first dose. Do not use the spray more than twice in 24 hours. If the first spray has no effect, do not try a second dose for the same attack, as it is unlikely to work.

If you have migraines

• Sumatriptan is used to treat headache pain during a migraine attack, not to stop the pain from coming on. You should wait until the migraine symptoms start to develop, rather than taking it when you feel that a migraine may be developing.

• Do not take other migraine treatments (such as other triptans or ergotamine) at the same time as sumatriptan.

• Some people may benefit from taking a non-steroidal anti-inflammatory painkiller (such as naproxen) in addition to sumatriptan. Your doctor will advise you about this if it is recommended for you.

• If you find that sumatriptan does not relieve your migraine, make an appointment to discuss this with your doctor, as an alternative medicine may be more effective for you.

• It may help to keep a migraine diary. Note down when and where each migraine attack started, what you were doing, and what you had eaten that day. A pattern may emerge and it may be possible for you to avoid some of the things that trigger your migraine attacks.

• Sumatriptan is used to treat migraine attacks once the pain has started, but there are other medicines available that may help to reduce the number of migraine attacks. If you have migraines frequently, discuss this with your doctor.

• Some people who get frequent migraine attacks are in fact getting medication-induced headache. Medication-induced headache (also called medication-overuse headache) is caused by taking painkillers or triptans too often. If you use sumatriptan or painkillers on more than two days a week on a regular basis, you may be at risk of this. You should talk with your doctor if you suspect it.

If you have cluster headaches

• Sumatriptan is usually given by injection for cluster headache, as it provides pain relief in about 5-15 minutes in most people.

• You will be shown how to use the injection. You should use it as soon as a headache occurs. The adult dose is one 6 mg injection for each headache. If you get more than one headache a day, the maximum dose you can have in 24 hours is two 6 mg injections. You must leave at least one hour between the two injections.

• You may also be prescribed another medicine to try to prevent the headaches from occurring. Preventative treatment is often taken over the period of the cluster headaches and is then stopped, although some treatments are taken longer-term.

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with sumatriptan. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

If you experience any other symptoms that you think may be due to the medicine, speak with your doctor or pharmacist for advice.

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