Sumatriptan side effects

Women holding bridge of nose as she suffers from a migraine
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If you’re suffering from a migraine headache, taking the drug sumatriptan may offer relief. 

By narrowing the blood vessels that send signals to your brain, sumatriptan can stop the pain and associated symptoms that occur when a migraine flares up. By decreasing the activity of the trigeminal nerve, the pain impulses you feel during an episode are prevented from reaching your central nervous system. 

Thanks to the medication, your body’s ability to register pain sensations is temporarily reduced, along with your perception of the migraine’s severity. This effect makes the drug – sold under the brand name Imigran – a popular choice for men and women in the UK.

But what side effects are associated with taking migraine medications like sumatriptan in its generic or branded form? Whether you prefer the 50mg or 100mg tablet version, nasal spray, or subcutaneous sumatriptan injection, the recommended weekly dose is two times per week.

Let’s examine why taking sumatriptan infrequently is a good idea, and detail the possible adverse effects associated with this migraine treatment.


Common side effects

The active ingredient contained in sumatriptan, sumatriptan succinate, belongs to a class of medication called 5HT (Serotonin) receptor agonists. In the UK, the supply of this medication is limited to avoid the risk of patients taking too much, which could increase the risk of serious side effects. 

A medication overuse headache could develop if you take sumatriptan too often. Whilst there is no set rule regarding consumption, best practice dictates that using sumatriptan for migraine relief shouldn’t become a daily activity. If you’re suffering from the effects of migraines on a regular basis, you should see your doctor or healthcare provider to discuss the maximum frequency of your dosage.

As with any medication, taking sumatriptan comes with the risk of side effects. Approximately one in ten may experience an adverse reaction after taking Imigran or generic sumatriptan medication. 

More commonly reported side effects include:

  • A sense of lethargy or lack of energy.
  • Nausea and vomiting.
  • Heaviness, pressure, or a feeling of tightening in the chest.
  • Dizziness or drowsiness.
  • Muscle aches or fever.
  • Feeling as though you’re intoxicated or in an altered state.
  • Shortness of breath.
  • Extreme changes in body temperature, whether hot or cold.
  • Pain or tingling in your fingers, toes, ears, nose, or jaw.


It is unlikely that you’ll experience any long-term side effects from taking sumatriptan. In the event that symptoms become prolonged – particularly those related to a tightening in the chest or chest pain – you should seek medical attention immediately.

Serious side effects of sumatriptan 

In rare cases taking sumatriptan for migraine relief could lead to more serious side effects. Since the medication functions by narrowing blood vessels, the resulting effect on blood flow could cause or worsen some medical conditions. If you have a history of respiratory or heart issues, you should consult your medical professional before using sumatriptan, especially in tandem with other medications.

The following side effects have been reported in rare cases:

  • Seizures, tremors, or muscle spasms.
  • Visual disturbances such as reduced or double vision. (In some cases these defects may be permanent, although they could be due to the migraine attack itself.)
  • Changes to heart rhythm (faster, slower, or irregular heartbeat).

If you have a narrowing of the arteries from a condition such as heart disease or angina, you should avoid taking sumatriptan. Individuals with a history of heart problems, those with uncontrolled high blood pressure or brain issues should also refrain from using the drug.

Sumatriptan and signs of an allergic reaction

Before taking sumatriptan to relieve the pain from a migraine attack, you should be aware of the signs that indicate a potentially adverse reaction:

  • Rash or hives on the skin.
  • Aggressive stomach pain.
  • Itchy or swollen eyelids.
  • Pressure or tightness in the chest. 
  • Swelling of the face, mouth, or lips.
  • Tightness or constriction in the throat.
  • Wheezing


If you experience these or other worrying symptoms after taking sumatriptan, call 999 or seek urgent medical attention.

Can sumatriptan cause long term side effects?

Sumatriptan itself is unlikely to cause long term side effects, but it can increase the risk of suffering a stroke or heart attack. These conditions can be life threatening and cause long term damage to your health.

In very rare cases, serious heart conditions have been reported after taking sumatriptan. Some individuals without a previous history of heart disease have developed permanent heart conditions after using the drug.

Approximately 1 in 10,000 people may experience liver function changes as a result of sumatriptan use. If you have a blood test to check your liver function, you should alert your healthcare professional that you are or have taken the drug.

Side effects of sumatriptan from drug interactions 

Being aware of medications that could cause adverse reactions when taken with sumatriptan will help you reduce the potential risk.

Here are some of the more commonly known drugs to avoid:

  • Serotonin-1 receptor agonists. Sumatriptan itself is a 5 HT receptor agonist, and so mixing the medication with similar drugs such as zolmitriptan or almotriptan is a bad idea. Combining other ‘triptans’ could worsen certain side effects, such as tightening or pressure in the chest. If you’ve taken another triptan, wait 24 hours before taking generic or branded sumatriptan.
  • Monoamine oxidase-A inhibitors (MAOIs). The drugs isocarboxazid, phenelzine, or tranylcypromine shouldn’t be taken with sumatriptan. The combination of an MAO inhibitor and a triptan could cause a severe condition known as serotonin syndrome. Symptoms include sweating, rapid heartbeat, or even hallucinations.
  • Ergot-containing drugs. Dihydroergotamine or methysergide and sumatriptan combined may increase the chance of experiencing side effects like pressure in the chest. If you’ve taken an ergot-containing medication you should wait 24 hours before taking Imigran or generic sumatriptan.

If you’re thinking of taking sumatriptan to treat your migraine, consult your doctor or healthcare professional to ensure your current medication won’t exacerbate a negative side effect.

The bottom line

Do you fall into a high-risk category due to a history of heart disease or high blood pressure? If this is the case, avoid sumatriptan unless you’ve consulted a medical professional first. Smokers, men over 40, and post-menopausal women should also let their doctor or pharmacist know that they’re interested in taking the medication.

To learn more about how sumatriptan can help the next time a migraine symptom surfaces, check out this handy guide. For more information, read our reviews page to learn more about how fellow users have found their experience with Imigran and generic sumatriptan.

Whilst all of our content is written and reviewed by healthcare professionals, it is not intended to be substituted for or used as medical advice. If you have any questions or concerns about your health, please speak to your doctor.