Imitrex (sumatriptan)

Imitrex Description

Imitrex is a drug prescribed commonly for the treatments of migraine headaches. Imitrex is the trade name of Sumatriptan, which is a sulfa drug. It is marketed in the United States by GlaxoSmithKline Corporation.

Sumatriptan in the drug is an agonist for a particular type of receptor (5-hydroxytryptamine1 receptor subtype) found in the cranial arteries and vasculature of the dura mater. These receptors mediate Vasoconstriction. Vasoconstriction is the process of narrowing of the blood vessels, which leads to decreased blood flow to that part of the body. Imitrex enhances this activity of the receptors. This is associated with the relief of migraine headache by reducing the vascular inflammation associated with migraine. The receptors are also present in the trigerminal nerve. Imitrex also acts on these. This explains the drug’s efficacy in the treatment of cluster headaches.

Conditions Treated by Imitrex

Imitrex is prescribed for the treatment of Migraine headaches. The mechanism by which it does this has already been discussed. Imitrex is to be used as a treatment for migraine headaches, after the attack has begun. Imitrex does not function as a preventive medicine to prevent or reduce the number of migraine attacks.

Imitrex Dosage Information

Imitrex is available in three dosages – 25, 50 and 100 mg tablets. The effect of the drug is dosage dependent with a higher dosage giving better efficiency. However, it is not advisable to take higher dosages because of the risk of side effects. The dosage varies from individual to individual.

a.) Typical Dosage Recommendations

Imitrex is to be used as and when required. Therefore, there is no daily dosage for the medicine. Depending on your doctor’s prescription, you may have to take a 25, 50 or 100mg dose. If the headache persists even after two hours, then you may have to repeat the dose. This may be repeated but the daily dose should not exceed 200mg.

b.) Missing A Dose

Imitrex is to be administered only in case of a migraine attack. Therefore, the question of time-dependence administration of the drug does not arise. However, there must be a gap of 2 hours between two administrations of the drug.

c.) Overdosing

Overdose of the drug can be fatal. You must seek medical attention immediately in case such a scenario arises. The symptoms of overdosing include but are not limited to tremors, difficulty in breathing, redness of the skin, vision problems, convulsions or seizures and weakness.

Sumatriptan has a very short half-life. Therefore, the patient must be monitored for 12hrs in case of an overdosing.

Imitrex Warnings

Imitrex should be administered only after the diagnosis of migraine headaches has been confirmed.

Imitrex should not be administered if the patient is known to have a previous history of myocardial ischemia or coronary artery disease (CAD). If the patient is at a risk of coronary artery disease as seen by the presence of risk factors such as hypertension, diabetes, obesity, a family history of coronary artery disease etc. then Imitrex should not be administered unless it has been verified that the patient does not have coronary artery disease. Cardiac ischemia, may not display any clinical symptoms. For such people who are at a risk of CAD or cardiac ischemia, it is recommended that the first dose of Imitrex be administered in the presence of trained medical professionals. Cases of severe cardiac events and fatalities have been reported on administering of Imitrex.

Imitrex possesses the ability to increase the blood pressure in the body. Therefore, administration of Imitrex to persons with uncontrolled hypertension is not recommended. The usage of Imitrex along with MAO-A inhibitors or within a period of two weeks after discontinuation of MAO-A inhibitors is contraindicated. Imitrex is also not recommended for patients with severe hepatic impairments.

Imitrex Side Effects

As mentioned earlier, Imitrex can have severe side effects and may be fatal too, in case of people who have myocardial ischemia. Imitrex may cause coronary artery vasospasm. Colonic ischemia and peripheral vascular ischemia have also been reported. The symptoms of these include bloody diarrhea and abdominal pain.

If you are taking selective serotonin reuptake inhibitors (SSRIs) or serotonin norepinephrine reuptake inhibitors (SNRIs) concomitantly with Imitrex, then you are at the risk of developing a Serotonin syndrome, which may be potentially life threatening. The symptoms of this include changes in your mental status such as hallucinations and getting agitated very easily, gastrointestinal symptoms such as vomiting, diarrhea or nausea, neuromuscular anomalies such as lack of coordination and hyperreflexia.

There have been reports of an increase in blood pressure on administration of the drug despite the patient not having a previous history of hypertension. Imitrex is contraindicated in patients with uncontrolled hypertension. Imitrex is known to induce hypersensitivity reactions in some people. The chances of this are higher if you have a previous history of being sensitive to multiple allergens. If you get any of the symptoms of an allergic reaction such as hives, swelling of your face, lips, or difficulty in breathing, then you must discontinue the medication immediately.

If you develop any of the symptoms mentioned above, then you must discontinue the medicine and consult your doctor immediately.

Possible Drug Interactions With Imitrex

Imitrex is known to cause vasospastic reactions. Ergot-containing drugs such as dihydroergotamine also have the same effect. Therefore, concomitant usage of the two may have additive effects and it should be avoided.

Monoamine Oxidase-A Inhibitors are prescribed for the treatment of depression. These however reduce the clearance of Sumatriptan in the body. This leads to Sumatriptan persisiting in the system for longer. This can result in adverse side effects. Hence, the administration of Imitrex if you are using Monoamine Oxidase-A Inhibitors is not advised.

Similarly, drugs of the selective serotonin reuptake inhibitor (SSRI) class such as Celexa (citalopram), these are used for the treatment of depression, must not be administered simultaneously with Imitrex. This may put you at a greater risk of developing Serotonin syndrome.

Many other drugs can interact with Imitrex. It is therefore very important that you discuss your medications with your doctor before undergoing therapy with Imitrex.

• Antidepressant Medication:
  • citalopram (Celexa)
  • desvenlafaxine (Pristiq)
  • duloxetine (Cymbalta)
  • escitalopram (Lexapro)
  • fluoxetine (Prozac)
  • fluvoxamine (Luvox)
  • paroxetine (Paxil)
  • sertraline (Zoloft)
  • venlafaxine (Effexor)

  This is not a complete list of all medications that may interact with Imitrex. Please notify all of your health care providers about the prescription and over-the-counter medications you currently take. This should include a complete list of all vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a treatment of a new medicine without properly notifying your primary health care professional or doctor.

If you have any questions about buying discount Imitrex online or any other prescription products you can contact our team of professional Patient Service Representatives or one of our pharmacists 24-7 by calling 1-800-226-3784.