Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Allergy: If you are allergic to sulphonamides (sulfa medications) you may experience an allergic reaction to sumatriptan. Reactions range from a skin allergy to a serious allergic reaction. If you are allergic to other medications in this class (5-hydroxytryptamine agonists such as rizatriptan and naratriptan) you can also have an allergic reaction to sumatriptan. If you are allergic to any of these medications, you should not take sumatriptan unless advised to do so by your doctor.
Blood pressure: Sumatriptan may cause an increase in blood pressure. If you have severe or uncontrolled high blood pressure, do not take sumatriptan.
Drowsiness/reduced alertness: Drowsiness may occur as a result of taking this medication. Avoid driving, operating machinery, or performing other hazardous tasks until you have determined how this medication affects you.
Heart disease: This medication may cause narrowing of the blood vessels that supply the heart. This can lead to chest pain, heart attacks, and other heart problems. For this reason, sumatriptan should not be used by people with heart or blood vessel disease. If you have certain risk factors for heart disease (e.g., high blood pressure, high cholesterol, smoking, obesity, diabetes, family history of coronary artery disease, menopause, men over 40 years of age), tell your doctor. If you experience symptoms of a heart attack (e.g., pain, pressure, tightness, or heaviness in the chest, jaw, neck, or shoulder; sweating; or shortness of breath), get immediate medical attention.
Injection: The injectable form of sumatriptan should never be taken intravenously (into a vein).
Kidney function: The effect of reduced kidney function on how sumatriptan acts in the body has not been evaluated. Sumatriptan is not recommended for use if you have reduced kidney function.
Liver function: Liver disease or reduced liver function may cause this medication to build up in the body, causing side effects. If you have liver problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication.
If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.
A lower dose of sumatriptan may be needed for people with reduced liver function. However, sumatriptan is not recommended for use if you have severely reduced liver function.
Medication overuse headaches: As with other pain relief medications, overuse of sumatriptan may lead to medication overuse headaches, or “rebound headaches” where the headache returns as the medication wears off. Avoid taking more of this medication than is recommended by your doctor. If you experience more frequent headaches, contact your doctor as soon as possible.
Seizures: There have been rare reports of seizures experienced by people taking this medication. Most of these people had a previous history of epilepsy or medical conditions that increase the risk of seizures. If you have a history of epilepsy or other condition that increases your risk for seizure, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Serotonin syndrome: People who use sumatriptan along with serotonin reuptake inhibitors (SSRIs; e.g., paroxetine, citalopram, fluoxetine), serotonin norepinephrine reuptake inhibitors (SNRIs; e.g., venlafaxine), or other medications that act on serotonin, may experience serotonin syndrome. This syndrome is severe and can be life-threatening. If you are taking antidepressants, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
If you experience symptoms of serotonin syndrome (e.g., agitation, hallucinations, fast heartbeat, fever, increased reflexes, nausea, vomiting, diarrhea) after using sumatriptan, get immediate medical attention.
Stroke and bleeding around the brain: Rarely, this medication may cause cerebrovascular events such as stroke and bleeding around the brain. If you have had a previous stroke or are at risk for it, talk to your doctor about the use of this medication. If you experience signs and symptoms of a stroke (e.g., sudden numbness or weakness, especially on one side of the body; sudden confusion or problems with speech; sudden vision problems in one or both eyes; sudden dizziness or loss of coordination; sudden severe headache, especially if it seems different from your usual headaches), get immediate medical attention.
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: This medication passes into breast milk. If you are a breast-feeding mother and are taking sumatriptan, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children and adolescents: The safety and effectiveness of this medication have not been established for adolescents and children under 18 years of age.
There is limited experience with the use of sumatriptan by people over 65 years of age. The use of this medication by seniors is not recommended.