Do not use Imitrex within 24 hours before or after using another migraine headache medicine, including:

• sumatriptan injection, almotriptan (Axert), eletriptan (Relpax), frovatriptan (Frova), naratriptan (Amerge), rizatriptan (Maxalt, Maxalt-MLT), or zolmitriptan (Zomig); or
• ergot medicine such as dihydroergotamine (D.H.E. 45, Migranal), ergotamine (Ergomar, Cafergot, Migergot), dihydroergotamine (D.H.E. 45, Migranal), or methylergonovine (Methergine).

Imitrex may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

You should not use Imitrex if you are allergic to sumatriptan, or if you have:

• coronary heart disease, angina (chest pain), blood circulation problems, lack of blood supply to the heart;
• a history of heart disease, heart attack, or stroke, including "mini-stroke";
• severe or uncontrolled high blood pressure;
• severe liver disease;
• ischemic bowel disease; or
• a headache that seems different from your usual migraine headaches.

Do not use Imitrex if you have used an MAO inhibitor such as furazolidone (Furoxone), isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate) in the last 14 days.

To make sure you can safely use Imitrex, tell your doctor if you have any of these other conditions:

• liver disease;
• kidney disease;
• epilepsy or other seizure disorder;
• high blood pressure, a heart rhythm disorder; or
• coronary heart disease (or risk factors such as diabetes, menopause, smoking, being overweight, having high cholesterol, having a family history of coronary artery disease, being older than 40 and a man, or being a woman who has had a hysterectomy).

FDA pregnancy category C. It is not known whether Imitrex will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication. Sumatriptan can pass into breast milk and may harm a nursing baby. Do not breast-feed within 12 hours after using Imitrex. If you use a breast pump during this time, throw out any milk you collect. Do not feed it to your baby. Imitrex should not be given to anyone under 18 or over 65 years of age.

Get emergency medical help if you have any of these signs of an allergic reaction to Imitrex: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using Imitrex and call your doctor if you have a serious side effect such as:

• feeling of pain or tightness in your jaw, neck, or throat;
• chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling;
• sudden numbness or weakness, especially on one side of the body;
• sudden severe headache, confusion, problems with vision, speech, or balance;
• sudden and severe stomach pain and bloody diarrhea;
• seizure (convulsions);
• numbness or tingling and a pale or blue-colored appearance in your fingers or toes; or
• (if you are also taking an antidepressant) - agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination, fainting.

Less serious Imitrex side effects may include:

• mild headache (not a migraine);
• pressure or heavy feeling in any part of your body;
• feeling hot or cold;
• dizziness, spinning sensation;
• drowsiness;
• nausea, vomiting, drooling;
• unusual taste in your mouth after using the nasal spray;
• burning, numbness, pain or other irritation in your nose or throat after using the nasal spray; or
• warmth, redness, or mild tingling under your skin.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.