In the U.S.—

• Vascular headache suppressant, migraine

Isometheptene, dichloralphenazone, and acetaminophen ( eye-soe-meth-EP-teen, dye-klor-al-FEN-a-zone, and a-seat-a-MIN-oh-fen ) combination is used to treat certain kinds of headaches, such as “tension” headaches and migraine headaches. This combination is not used regularly (for example, every day) to prevent headaches. It should be taken only after headache pain begins, or after a warning sign that a migraine is coming appears. Isometheptene helps to relieve throbbing headaches, but it is not an ordinary pain reliever. Dichloralphenazone helps you to relax, and acetaminophen relieves pain.

This medicine is available only with your doctor's prescription, in the following dosage form:

Oral
• Capsules (U.S.)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this combination medicine, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to acetaminophen or to this combination medicine. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Studies with this combination medicine have not been done in either humans or animals.

Breast-feeding—Acetaminophen passes into the breast milk in small amounts. However, this medicine has not been shown to cause problems in nursing babies.

Children—Studies with this medicine have been done only in adult patients, and there is no specific information about its use in children.

Older adults—Many medicines have not been tested in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of this combination medicine in the elderly with use in other age groups.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this combination medicine, it is especially important that your health care professional know if you are taking any of the following:

• Monoamine oxidase (MAO) inhibitor activity (isocarboxazid [e.g., Marplan], phenelzine [e.g., Nardil], procarbazine [e.g., Matulane], selegiline [e.g., Eldepryl], tranylcypromine [e.g., Parnate])—Taking this combination medicine while you are taking or within 2 weeks of taking a monoamine oxidase (MAO) inhibitor may increase the chance of side effects

• Alcohol abuse or
• Heart attack (recent) or
• Heart or blood vessel disease or
• Kidney disease or
• Liver disease or
• Stroke (recent) or
• Virus infection of the liver (viral hepatitis)—The chance of side effects may be increased

• Glaucoma, not well controlled, or
• High blood pressure (hypertension), not well controlled—The isometheptene in this combination medicine may make these conditions worse

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often than directed, and do not take it every day for several days in a row. If the amount you are to take does not relieve your headache, check with your doctor. If a headache medicine is used too often, it may lose its effectiveness or even cause a type of physical dependence. If this occurs, your headaches may actually get worse. Also, taking too much acetaminophen can cause liver damage.

This medicine works best if you:

• Take it as soon as the headache begins. If you get warning signals of a migraine, take this medicine as soon as you are sure that the migraine is coming. This may even stop the headache pain from occurring.
• Lie down in a quiet, dark room until you are feeling better.

People who get a lot of headaches may need to take a different medicine to help prevent headaches. It is important that you follow your doctor's directions, even if your headaches continue to occur. Headache-preventing medicines may take several weeks to start working. Even after they do start working, your headaches may not go away completely. However, your headaches should occur less often, and they should be less severe and easier to relieve, than before. This will reduce the amount of headache relievers that you need. If you do not notice any improvement after several weeks of headache-preventing treatment, check with your doctor.

Dosing—

The dose of this combination medicine 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 this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

• For “tension” headaches:
  • Adults: 1 or 2 capsules every 4 hours, as needed. Not more than 8 capsules a day.
  • Children: Dose must be determined by the doctor.
• For migraine headaches:
  • Adults: 2 capsules for the first dose, then 1 capsule every hour, as needed. Not more than 5 capsules in 12 hours.
  • Children: Dose must be determined by the doctor.

Storage—

To store this medicine

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat and moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Check with your doctor:

• If the medicine stops working as well as it did when you first started using it. This may mean that you are in danger of becoming dependent on the medicine. Do not try to get better relief by increasing the dose.
• If you are having headaches more often than you did before you started using this medicine. This is especially important if a new headache occurs within 1 day after you took your last dose of headache medicine, headaches begin to occur every day, or a headache continues for several days in a row. This may mean that you are dependent on the medicine. Continuing to take this medicine will cause even more headaches later on. Your doctor can give you advice on how to relieve the headaches.

Check the labels of all nonprescription (over-the-counter [OTC]) and prescription medicines you now take. Taking other medicines that contain acetaminophen together with this medicine may lead to an overdose. If you have any questions about this, check with your health care professional.

This medicine may cause some people to become drowsy, dizzy, or less alert than they are normally. These effects may be especially severe if you also take CNS depressants (medicines that slow down the nervous system, possibly causing drowsiness) together with this medicine. Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; muscle relaxants; antiemetics (medicines that prevent or relieve nausea or vomiting), and anesthetics. If you are not able to lie down for a while, make sure you know how you react to this medicine or combination of medicines before you drive, use machines, or do anything else that could be dangerous if you are drowsy or dizzy or are not alert.

Do not drink alcoholic beverages while taking this medicine. To do so may increase the chance of liver damage caused by acetaminophen, especially if you drink large amounts of alcoholic beverages regularly. Also, because drinking alcoholic beverages may make your headaches worse or cause new headaches to occur, people who often get headaches should probably avoid alcohol.

Along with its needed effects, a medicine 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 as soon as possible if any of the following side effects occur:

• Less common
  • Unusual tiredness or weakness 
  
  

• Rare
  • Black, tarry stools;  blood in urine or stools;  pinpoint red spots on skin;  skin rash, hives, or itching;  sore throat and fever;  unusual bleeding or bruising;  yellow eyes or skin 
  
  

• Symptoms of dependence on this medicine
  • Headaches, more severe and/or more frequent than before 
  
  

• Symptoms of acetaminophen overdose
  • Diarrhea;  increased sweating;  loss of appetite;  nausea or vomiting ;  pain, tenderness, and/or swelling in the upper abdominal (stomach) area;  stomach cramps or pain  
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common
  • Drowsiness 
  
  

• Rare
  • Dizziness;  fast or irregular heartbeat  
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.