Imitrex Side Effects

Generic name: sumatriptan

Medically reviewed by Drugs.com. Last updated on Mar 5, 2025.

Note: This document provides detailed information about Imitrex Side Effects associated with sumatriptan. Some dosage forms listed on this page may not apply specifically to the brand name Imitrex.

Applies to sumatriptan: nasal powder, nasal spray.

Other dosage forms:

• oral tablet
• subcutaneous kit, subcutaneous solution

Precautions

It is very important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to use it. Blood and urine tests may be needed to check for unwanted effects.

Do not use this medicine if you have taken other triptan or ergot-type migraine medicines within the past 24 hours. Some examples of triptan medicines are almotriptan (Axert®), eletriptan (Relpax®), frovatriptan (Frova®), naratriptan (Amerge®), rizatriptan (Maxalt®), sumatriptan (the active ingredient contained in Imitrex) naproxen (Treximet®), or zolmitriptan, (Zomig®). Some examples of ergot-type medicines are dihydroergotamine (D.H.E. 45®, Migranal®), ergotamine (Bellergal®, Cafergot®, Ergomar®, Wigraine®), or methysergide (Sansert®). Also, do not use this medicine if you have taken a MAO-A inhibitor (eg, Nardil®, Parnate®) in the past 14 days.

This medicine may cause a serious type of allergic reaction called anaphylaxis, which can be life-threatening and requires immediate medical attention. The most serious signs of this reaction are very fast or irregular breathing, gasping for breath, or fainting. Other signs may include: changes in facial skin color, very fast but irregular heartbeat or pulse, hive-like swellings on the skin, and puffiness or swellings of the eyelids or around the eyes. If these side effects occur, get emergency help at once.

Check with your doctor if you have used this medicine and your migraine got worse or started occurring more often.

This medicine may cause problems if you have heart disease. If your doctor thinks you might have a problem with this medicine, he or she may want you to take your first dose in the doctor’s office or clinic.

This medicine may increase your risk of having an abnormal heart rhythm, heart attack, angina, or stroke. This is more likely to occur if you or a family member already has heart disease, if you have diabetes, high blood pressure, or if you smoke. Call your doctor right away if you have any symptoms of a heart problem, such as chest pain or discomfort, an uneven heartbeat, nausea or vomiting, pain or discomfort in the shoulders, arms, jaw, back, or neck, shortness of breath, or sweating. Call your doctor right away if you have any symptoms of a stroke, such as confusion, difficulty with speaking, double vision, headaches, an inability to move the arms, legs, or facial muscles, an inability to speak, or slow speech.

Check with your doctor right away if you have chest discomfort, jaw or neck tightness after using this medicine. Also, tell your doctor if you have sudden or severe abdominal or stomach pain or bloody diarrhea after using this medicine.

Using sumatriptan alone or in combination with other migraine medicines for 10 or more days per month may lead to worsening of headaches. You may keep a headache diary to record the headache frequency and drug use.

Make sure your doctor knows about all the other medicines you are using. Sumatriptan may cause a serious condition called serotonin syndrome when taken with some medicines. This especially includes medicines used to treat depression, such as citalopram, duloxetine, escitalopram, fluoxetine, fluvoxamine, olanzapine, paroxetine, sertraline, venlafaxine, Celexa®, Cymbalta®, Effexor®, Lexapro®, Luvox®, Paxil®, Prozac®, Sarafem®, Symbyax®, or Zoloft®. Check with your doctor right away if you have agitation, confusion, diarrhea, excitement while talking that is not normal, fever, overactive reflexes, poor coordination, restlessness, shivering, sweating, trembling or shaking that you cannot control, or twitching. These could be symptoms of serotonin syndrome.

Check with your doctor immediately if blurred vision, difficulty in reading, or any other change in vision occurs during or after your treatment. Your eyes may need to be checked by an ophthalmologist (eye doctor).

Drinking alcoholic beverages can make headaches worse or cause new headaches to occur. People who suffer from severe headaches should probably avoid alcoholic beverages, especially during a headache.

Some people feel dizzy or drowsy during or after a migraine, or using sumatriptan to relieve a migraine. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Common side effects of Imitrex

Some side effects of sumatriptan may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Serious side effects of Imitrex

Along with its needed effects, sumatriptan may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking sumatriptan:

For healthcare professionals

Applies to sumatriptan: nasal capsule, nasal spray, oral tablet, subcutaneous kit, subcutaneous solution, transdermal film extended release.

General adverse events

The more commonly observed adverse reactions have included those of pressure sensation, flushing, tingling, dizziness/vertigo, warm/hot sensation, burning sensation, flushing, and numbness; formulation specific events including injection site reactions, application site pain, and nasal discomfort have been reported.^[Ref]

Cardiovascular

• Common (1% to 10%): Chest pain/tightness/pressure and/or heaviness, flushing, neck/throat/jaw pain/tightness/pressure, transient increases in blood pressure (arising soon after treatment)
• Uncommon (0.1% to 1%): Bradycardia, hypertension, hypotension, palpitations, pulsating sensations, tachycardia, various transient ECG changes (nonspecific ST or T-wave changes, prolongation of PR or QTc intervals, sinus arrhythmia, nonsustained ventricular premature beats, isolated junctional ectopic beats, atrial ectopic beats, delayed activation of the right ventricle)
• Rare (less than 0.1%): Abnormal pulse, arrhythmia, pallor, Raynaud's phenomenon, vasodilation
• Frequency not reported: Abdominal aortic aneurysm, angina, atherosclerosis, cerebrovascular lesion, coronary artery vasospasm, edema, heart block, peripheral cyanosis, phlebitis, thrombosis, transient myocardial ischemia
• Postmarketing reports: Cyanosis, hypotension, myocardial infarction, palpitations^[Ref]

Life-threatening disturbances of cardiac rhythm, such as ventricular tachycardia and ventricular fibrillation leading to death, and rare reports of acute myocardial infarction, have been reported within a few hours after administration of 5-HT1 agonists.

Chest discomfort is usually noncardiac in origin. A survey of 453 migraine patients found chest symptoms occurred in up to 58% of patients in at least some attacks and in up to 42% of patients in all attacks.

One study of 735 consecutive migraine patients reported that chest symptoms are frequent, but rarely important adverse effects of (primarily subcutaneous) sumatriptan (the active ingredient contained in Imitrex) The risk of chest symptoms was reported to be patient dependent and not related, even opposite, to cardiovascular disease. This report contradicts the hypothesis that chest symptoms after sumatriptan are caused by cardiac ischemia.

Another study of 125 patients concluded that panic-like symptoms may explain the chest pain and related side effects after sumatriptan administration in patients with high levels of anxiety.^[Ref]

Nervous system

• Very common (10% or more): Dizziness (10%), abnormal taste (20%; nasal powder)
• Common (1% to 10%): Bad/unusual taste, drowsiness/sedation, dystonia, headache, hypoesthesia, paraesthesia (all types), tremor
• Uncommon (0.1% to 1%): Syncope
• Rare (less than 0.1%): Difficulties in concentration, disturbances of smell, dysarthria, dysesthesia, hyperesthesia, monoplegia/diplegia, myoclonia, transient hemiplegia
• Frequency not reported: Bradylogia, cerebral ischemia, cerebrovascular lesion, cluster headache, convulsions, facial paralysis, incoordination, increased alertness, memory disturbance, migraine, motor dysfunction, neuralgia, nystagmus, paralysis, radiculopathy, raised intracranial pressure, seizures, speech disturbance
• Postmarketing reports: Central nervous system vasculitis, cerebellar infarction, cerebrovascular accident, subarachnoid hemorrhage, serotonin syndrome, temporal arteritis^[Ref]

Cerebral hemorrhage, subarachnoid hemorrhage, and stroke have occurred with 5-HT1 treatment; some have resulted in fatalities. One case of sumatriptan-induced cortical stroke has been reported in a patient with sagittal sinus thrombosis. In some cases, it appears possible that the cerebrovascular events were primary, and the 5-HT1 agonist administered in the belief that presenting symptoms were due to migraine when they were not. Patients with migraine may also be at an increased risk of certain cerebrovascular events such as stroke, hemorrhage, and transient ischemic attacks.

Medication overuse headache may present as migraine-like headaches or as a marked increase in frequency of migraine attacks.

Serotonin syndrome is characterized by mental status changes (e.g., agitation, hallucinations, coma), autonomic instability (e.g., tachycardia, labile blood pressure, hyperthermia), neuromuscular aberrations (e.g., hyperreflexia, incoordination), and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). The onset of symptoms generally occurs within minutes to hours of receiving a new or a greater dose of a serotoninergic medications.

Seizures have been reported in patients with either a history of seizures or concurrent conditions predisposing to seizures and also in patients where no such predisposing factors are apparent.^[Ref]

Gastrointestinal

• Common (1% to 10%): Abdominal discomfort, dysphagia, nausea and/or vomiting
• Uncommon (0.1% to 1%): Diarrhea, gastroesophageal reflux
• Rare (less than 0.1%): Flatulence/eructation, gallstones, peptic ulcer, retching
• Frequency not reported: Abdominal distention, colitis, constipation, dental pain, disorder of mouth and tongue (e.g., burning of tongue, numbness of tongue, dry mouth), dyspeptic symptoms, feelings of gastrointestinal pressure, gastritis, gastroenteritis, gastrointestinal bleeding, gastrointestinal pain, hematemesis, hypersalivation, hyposalivation, intestinal obstruction, ischemic colitis, melena, oral itching and irritation, pancreatitis, salivary gland swelling, swallowing disorders^[Ref]

It is unclear whether the nausea and vomiting is related to sumatriptan (the active ingredient contained in Imitrex) therapy or to the underlying condition.

One report has suggested that "throat tightness" and chest pain associated with sumatriptan may sometimes be attributable to changes in esophageal motility.^[Ref]

Other

• Very common (10% or more): Atypical sensations such as tingling, warm or hot sensations, vertigo
• Common (1% to 10%): Atypical sensations such as burning sensation, chills, facial pain, fatigue, feeling of pressure, feeling strange, jaw discomfort, malaise, neck pain/stiffness, numbness, pain and other pressure sensations, pain where the location is specified, prickling sensations, stinging sensations, sensation of lightness, tight feeling in head, tightness or heaviness, weakness
• Rare (less than 0.1%): Fever, intoxication, simultaneous hot and cold sensations, swelling of the extremities, tickling sensations
• Frequency not reported: Abortion, contusions, ear infection, ear, nose, and throat hemorrhage, external otitis, feeling of fullness in the ear(s), hearing disturbances, hearing loss, Meniere's disease, otalgia, overdose, photophobia, sensitivity to noise, swelling of face, tinnitus
• Postmarketing reports: Deafness^[Ref]

Dermatologic

• Very common (10% or more): Application site pain (26%; transdermal patch)
• Common (1% to 10%): Sweating, allergic contact dermatitis and application site paresthesia/pruritus/warmth/discomfort/irritation/site discoloration (transdermal patch)
• Uncommon (0.1% to 1%): Eruptions, erythema, pruritus, skin rashes
• Rare (less than 0.1%): Skin tenderness
• Frequency not reported: Dry/scaly skin, eczema, hematoma, hyperhidrosis, seborrheic dermatitis, skin nodules, tightness of skin, wrinkling of skin
• Postmarketing reports: Allergic vasculitis, angioedema, exacerbation of sunburn, photosensitivity, urticaria, burns scars, severe redness, pain, skin discoloration, blistering and cracked skin with the iontophoretic transdermal system^[Ref]

Burns and scars have been reported on the skin where the transdermal iontophoretic transdermal system has been worn. These reports describe severe redness, pain, skin discoloration, blistering, and cracked skin. On June 13, 2016, the manufacturer of the patch suspended sales and distribution of the patch to investigate the cause of these reports.^[Ref]

Endocrine

• Frequency not reported: Elevated thyrotropin stimulating hormone (TSH) levels, endocrine cysts, lumps, and masses, hypothyroidism^[Ref]

Genitourinary

• Rare (less than 0.1%): Dysmenorrhea, dysuria
• Frequency not reported: Abnormal menstrual cycle, bladder inflammation, breast swelling, breast tenderness, cysts, disorder of breasts, endometriosis, galactorrhea, hematuria, increased urination, inflammation of fallopian tubes, intermenstrual bleeding, lumps, masses of breasts, menstruation symptoms, micturition disorders, nipple discharge, urethritis, urinary infections^[Ref]

Hematologic

• Frequency not reported: Anemia, lymphadenopathy
• Postmarketing reports: Hemolytic anemia, pancytopenia, thrombocytopenia^[Ref]

Hepatic

• Uncommon (0.1% to 1%): Minor disturbances in liver function tests^[Ref]

Hypersensitivity

• Frequency not reported: Hypersensitivity reactions ranging from cutaneous hypersensitivity to anaphylaxis^[Ref]

Immunologic

• Rare (less than 0.1%): Influenza
• Frequency not reported: Herpes^[Ref]

Local

• Very common (10% or more): Injection site reaction
• Common (1% to 10%): Burning sensation (nasal administration)
• Frequency not reported: Injection site stinging/burning, swelling, erythema, bruising, and bleeding

Postmarketing reports:

Following subcutaneous administration: Contusion, induration, lipoatrophy, lipohypertrophy, pain, redness, stinging, subcutaneous bleeding, swelling^[Ref]

Local irritative symptoms were reported in clinical trials with sumatriptan nasal spray in approximately 5% of patients, and were severe in about 1% of cases. Symptoms were noted as being transient and generally resolved in less than 2 hours.^[Ref]

Metabolic

• Uncommon (0.1% to 1%): Thirst
• Rare (less than 0.1%): Dehydration, hunger, polydipsia, reduced appetite
• Frequency not reported: Fluid disturbances, fluid retention, hyperglycemia, hypoglycemia, weight gain, weight loss^[Ref]

Musculoskeletal

• Common (1% to 10%): Muscle cramps, myalgia
• Uncommon (0.1% to 1%): Joint disturbances (pain, stiffness, swelling, ache)
• Rare (less than 0.1%): Backache, muscle stiffness, muscle tiredness, need to flex calf muscles
• Frequency not reported: Acquired musculoskeletal deformity, arthralgia, arthritis, articular rheumatitis, difficulty in walking, intervertebral disc disorder, muscle atrophy, muscle tightness and rigidity, musculoskeletal inflammation, rigidity, tetany, twitching^[Ref]

Ocular

• Common (1% to 10%): Vision alterations
• Uncommon (0.1% to 1%): Irritation of the eye, lacrimation, photophobia
• Frequency not reported: Accommodation disorders, blindness, conjunctivitis, diplopia. disorders of sclera, low vision, eye edema and swelling, eye hemorrhage, eye itching, eye pain, external ocular muscle disorders, flickering, keratitis, mydriasis, scotoma, visual disturbances
• Postmarketing reports: Ischaemic optic neuropathy, retinal artery occlusion, retinal vein thrombosis^[Ref]

Loss of vision included reports of permanent defects. Causality has not been established as visual disorders may occur during a migraine attack itself.^[Ref]

Oncologic

• Frequency not reported: Neoplasm of pituitary, primary malignant breast neoplasm^[Ref]

Psychiatric

• Common (1% to 10%): Anxiety
• Uncommon (0.1% to 1%): Agitation, euphoria, mental confusion, relaxation
• Rare (less than 0.1%): Depression, globus hystericus, hysteria, sleep disturbance
• Frequency not reported: Aggressiveness, apathy, depressive disorders, detachment, disturbance of emotions, drug abuse, hallucinations, neurotic disorders, personality change, phobia, psychomotor disorders, stress, suicide^[Ref]

Renal

• Rare (less than 0.1%): Renal calculus
• Postmarketing reports: Acute renal failure^[Ref]

Respiratory

• Very common (10% or more): Nasal discomfort (up to 11%; nasal powder)
• Common (1% to 10%): Bronchospasm, disorder/discomfort of nasal cavity/sinuses (nasal administration, subcutaneous administration), dyspnea, throat discomfort (nasal administration); rhinitis (nasal administration), rhinorrhea (nasal administration)
• Rare (less than 0.1%): Diseases of the lower respiratory tract, hiccoughs, yawning
• Frequency not reported: Allergic rhinitis, asthma, breathing disorder, bronchitis, cough, nasal inflammation, sinusitis, upper respiratory tract inflammation, voice disturbances
• Postmarketing reports: Shortness of breath (as part of hypersensitivity reaction)^[Ref]

The consequences of repeated and prolonged use of the nasal spray on nasal and/or respiratory mucosa have not been established.^[Ref]

See also:

Frequently asked questions

• How often can you take Imitrex (sumatriptan)?
• Ubrelvy vs Imitrex (sumatriptan): How do they compare?
• How long does Imitrex (sumatriptan) take to work?
• Why does Imitrex (sumatriptan) make me feel weird?
• Can Imitrex (sumatriptan) cause rebound headaches?
• What are the brands of sumatriptan?
• What are the new drugs for the treatment of migraine?

Further information

Imitrex side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

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