Naratriptan

Naratriptan is a prescription medicine used to treat migraine headaches in adults.  Naratriptan belongs to a group of drugs called 5-HT agonists or "triptans".  It is believed to work by causing dilated blood vessels in the brain to narrow.

Naratriptan comes in tablet form and is taken by mouth as soon as a migraine starts.

Common side effects of naratriptan include dizziness, feeling hot or cold, and light sensitivity.

Naratriptan may be found in some form under the following brand names:

• Amerge

If you take too much naratriptan, call your healthcare provider or go to the nearest hospital emergency room right away.

You should not use this medicine if you are allergic to naratriptan, or if you have:

• severe or uncontrolled high blood pressure;

• past or present heart problems;

• history of coronary artery disease, heart attack, or stroke, including "mini-stroke";

• Wolff-Parkinson-White syndrome or other heart rhythm disorder;

• a blood vessel disorder or circulation problems that cause a lack of blood supply within the body;

• severe liver or kidney disease; or

• a headache that seems different from your usual migraine headaches.

To make sure naratriptan is safe for you, tell your doctor if you have:

• liver or kidney disease;

• 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).

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether naratriptan passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.

Do not give this medicine to anyone younger than 18.

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

• medicines like naratriptan--almotriptan, eletriptan, frovatriptan, rizatriptan, sumatriptan, zolmitriptan, and others; or

• ergot medicine--dihydroergotamine, ergotamine, ergonovine, methylergonovine.

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

In the U.S.

• Amerge

Available Dosage Forms:

• Tablet

Therapeutic Class: Antimigraine

Pharmacologic Class: Serotonin Receptor Agonist, 5-HT1

Take naratriptan only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered. Using too much naratriptan may increase the chance of side effects.

Do not use naratriptan for a headache that is different from your usual migraines. Talk to your doctor about what to do for regular headaches.

To relieve your migraine as soon as possible, take naratriptan with water or other liquids as soon as the headache pain begins. Even if you get warning signals of a coming migraine (an aura), you should wait until the headache pain starts before using naratriptan.

Ask your doctor ahead of time about any other medicine you may take if naratriptan does not work. After you take the other medicine, check with your doctor as soon as possible. Headaches that are not relieved by naratriptan are sometimes caused by conditions that need other treatment.

If you feel much better after a dose of naratriptan, but your headache comes back or gets worse after a while, you may take one additional dose of naratriptan 4 hours after the first dose. Do not use more than 5 milligrams in any 24-hour period.

naratriptan comes with a patient information leaflet. It is very important that you read and understand this information. Be sure to ask your doctor about anything you do not understand.

Dosing

The dose of naratriptan will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of naratriptan. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage form (tablets):
  • For migraine headaches:
    • Adults—1 or 2.5 milligrams (mg) taken as a single dose. If the migraine comes back after being relieved, another dose may be taken 4 hours after the last dose. Do not take more than 5 mg in any 24-hour period.
    • Children—Use and dose must be determined by your doctor.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

• Tell all of your health care providers that you take naratriptan. This includes your doctors, nurses, pharmacists, and dentists.
• Very bad and sometimes deadly allergic side effects have rarely happened. Talk with your doctor.
• Avoid driving and doing other tasks or actions that call for you to be alert until you see how this medicine affects you.
• This medicine is not meant to prevent or lower the number of migraine headaches you get. Talk with your doctor.
• Use care if you have risks for heart disease (high blood pressure, high cholesterol, overweight, high blood sugar or diabetes, cigarette smoking, man older than 40 years of age, other family members with early heart disease, woman after change of life). Talk with your doctor.
• Taking more of naratriptan (a higher dose, more often) than your doctor told you to take may cause your headaches to become worse.
• Have your blood pressure checked often. Talk with your doctor.
• If you are 65 or older, use this medicine with care. You could have more side effects.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using naratriptan while you are pregnant.
• Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

Use this medicine as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• Take with or without food.
• Swallow whole. Do not chew, break, or crush.
• Take with liquids as early as you can after the attack has started.
• If your headache comes back after the first dose, 1 more dose may be taken 4 hours after the first one.

What do I do if I miss a dose?

• This medicine is taken on an as needed basis. Do not take more often than told by the doctor.

1 mg white to off-white tablets, capsule shaped, film-coated, and debossed with "N" on one side and "1" on the other side

2.5 mg green tablets, capsule shaped, film-coated, and debossed with "N" on one side and "2.5" on the other side

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenesis

In carcinogenicity studies, mice and rats were given Naratriptan by oral gavage for 104 weeks. There was no evidence of an increase in tumors related to Naratriptan administration in mice receiving up to 200 mg/kg/day. That dose was associated with a plasma (AUC) exposure that was 110 times the exposure in humans receiving the MRDD of 5 mg. Two rat studies were conducted, one using a standard diet and the other a nitrite-supplemented- diet (Naratriptan can be nitrosated in vitro to form a mutagenic product that has been detected in the stomachs of rats fed a high-nitrite diet). Doses of 5, 20, and 90 mg/kg were associated with AUC exposures that in the standard-diet study were 7, 40, and 236 times, respectively, and in the nitrite-supplemented-diet study were 7, 29, and 180 times, respectively, the exposure in humans at the MRDD. In both studies, there was an increase in the incidence of thyroid follicular hyperplasia in high-dose males and females and in thyroid follicular adenomas in high-dose males. In the standard-diet study only, there was also an increase in the incidence of benign c-cell adenomas in the thyroid of high-dose males and females. The exposures achieved at the no-effect dose for thyroid tumors were 40 (standard diet) and 29 (nitrite-supplemented diet) times the exposure achieved in humans at the MRDD. In the nitrite-supplemented diet study only, the incidence of benign lymphocytic thymoma was increased in all treated groups of females. It was not determined if the nitrosated product is systemically absorbed. However, no changes were seen in the stomachs of rats in that study.

Mutagenesis

Naratriptan was not mutagenic when tested in in vitro gene mutation (Ames and mouse lymphoma tk) assays. Naratriptan was also negative in the in vitro human lymphocyte assay and the in vivo mouse micronucleus assay. Naratriptan can be nitrosated in vitro to form a mutagenic product (WHO nitrosation assay) that has been detected in the stomachs of rats fed a nitrite-supplemented diet.

Impairment of Fertility

In a reproductive toxicity study in which male and female rats were administered Naratriptan orally prior to and throughout the mating period (10, 60, 170, or 340 mg/kg/day; plasma exposures [AUC] approximately 11, 70, 230, and 470 times, respectively, the human exposure at the MRDD), there was a drug-related decrease in the number of females exhibiting normal estrous cycles at doses of 170 mg/kg/day or greater and an increase in preimplantation loss at 60 mg/kg/day or greater. In high-dose males, testicular/epididymal atrophy accompanied by spermatozoa depletion reduced mating success and may have contributed to the observed preimplantation loss. The exposures achieved at the no-effect doses for preimplantation loss, anestrus, and testicular effects were approximately 11, 70, and 230 times, respectively, the exposures in humans at the MRDD.

In a study in which rats were dosed orally with Naratriptan (10, 60, or 340 mg/kg/day) for 6 months, changes in the female reproductive tract including atrophic or cystic ovaries and anestrus were seen at the high dose. The exposure at the no-effect dose of 60 mg/kg was approximately 85 times that in humans at the MRDD.

Naratriptan tablets, USP containing 1 mg and 2.5 mg of Naratriptan (base) as the hydrochloride salt.

Naratriptan Tablets USP, 1 mg, are white to off-white colored, capsule shaped, film-coated tablets debossed with “N” on one side and “1” on the other side are supplied as:

Carton of 9 Unit-of-Use tablets each with  cross perforation and individually labeled NDC 42043-130-09

Naratriptan Tablets USP, 2.5 mg, are green colored, capsule shaped, film-coated tablets debossed with “N” on one side and “2.5” on the other side are supplied as:

Carton of 9 Unit-of-Use tablets each with cross perforation and individually labeled NDC 42043-131-09

Store at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature].

(NAR a trip tan)

Applies to naratriptan: oral tablet

Along with its needed effects, naratriptan 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 naratriptan:

• Chest pain (severe)
• heaviness, tightness, or pressure in the chest, throat, or neck
• sensation of burning, warmth, heat, numbness, tightness, or tingling

• Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings

• Convulsions (seizures)
• irregular heartbeat
• slow heartbeat

Some side effects of naratriptan 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:

• Anxiety
• bone pain
• change in taste sensation
• chills or fever
• difficulty with sleeping
• eye problems
• fainting
• general feeling of discomfort or illness
• joint pain
• muscle or joint stiffness, tightness, or rigidity
• pounding heartbeat
• stomach discomfort or pain
• trembling or shaking of the hands or feet
• unusual tiredness or weakness