GENERIC NAME: ISOMETHEPTENE/ ACETAMINOPHEN/ DICHLORALPHENAZONE - ORAL (a-SEET-a-MIN-oh-fen/EYE-soe-meth-EP-teen/ DYE-klor-al-FEN-a-zone)
BRAND NAME(S): Amidrine, Isocom, Midchlor, Midrin
USES: This combination medication is used to relieve tension and migraine headaches. Acetaminophen helps to decrease the pain from the headache. Isometheptene helps to narrow the widened blood vessels in the head. Headache pain can be caused by these widened blood vessels. Dichloralphenazone helps to relax the body.
HOW TO USE: Take this medication by mouth with or without food as directed by your doctor.Dosage is based on your medical condition and response to therapy.For migraine headaches, take at the first sign of the headache as directed by your doctor. Then you will usually take 1 capsule every hour as needed until the headache is relieved, or take as directed by your doctor. Do not take more than 5 capsules in a 12-hour period.For tension headaches, take every 4 hours as needed or as directed by your doctor. Do not take more than 8 capsules in a 24-hour period.This medication may cause withdrawal reactions, especially if it has been used regularly for a long time (longer than 2 weeks) or in high doses. In such cases, withdrawal symptoms (such as mental/mood changes, shaking, seizures) may occur if you suddenly stop using this medication. To prevent withdrawal reactions, your doctor may reduce your dose gradually. Consult your doctor or pharmacist for more details, and report any withdrawal reactions immediately.Though it is very unlikely to occur, this medication can also result in abnormal drug-seeking behavior (addiction/habit forming). Do not increase your dose, take it more frequently, or use it for a longer time than prescribed. Properly stop the medication when so directed. This will lessen the chances of becoming addicted.This medication contains acetaminophen. Do not take more acetaminophen than recommended because this may increase your risk of developing liver problems. (See also Side Effects section.)Inform your doctor if you notice increased use of this medication, the medication not working as well, a worsening of headaches, an increase in the number of headaches, or use of this medication for more than 2 headache episodes a week. Your doctor may need to change your medication and/or add a separate medication to prevent the headaches.
SIDE EFFECTS: Dizziness, drowsiness, and nausea may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor immediately if any of these unlikely but serious side effects occur: easy bruising/bleeding, signs of infection (e.g., fever, persistent sore throat), mental/mood changes, fast/irregular heartbeat.If you do not have liver problems, do not take more than 4 grams (4000 milligrams) of acetaminophen per day. If you take more than the maximum daily amount, it may cause serious (possibly fatal) liver disease. Seek immediate medical attention if you have any of the following symptoms of liver damage: severe nausea/vomiting, yellowing eyes/skin, dark urine, stomach pain, extreme tiredness.If you have liver problems, consult your doctor or pharmacist for a safe dosage of this medication.A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking this medication, tell your doctor or pharmacist if you are allergic to acetaminophen, isometheptene, or dichloralphenazone; or to chloral hydrate; or if you have any other allergies.This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: a certain eye disease (glaucoma).Before using this medication, tell your doctor or pharmacist your medical history, especially of: heart/blood vessel disease (e.g., coronary artery disease, stroke, recent heart attack), kidney disease, liver disease, high blood pressure, history of drug abuse, depression, stomach/esophagus problems (e.g., ulcers, esophagitis).This drug may make you dizzy or drowsy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages. Remember that alcohol may be a cause of headaches.This product contains acetaminophen, which may cause liver damage. Daily use of alcohol, especially when combined with acetaminophen, may increase your risk for liver damage. Limit alcohol. Check with your doctor or pharmacist for more information.Before having surgery, tell your doctor or dentist that you are using this medication.During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.This medication passes into breast milk. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: Your healthcare professionals (e.g., doctor or pharmacist) may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop or change the dosage of any medicine before checking with them first.This drug should not be used with the following medications because very serious interactions may occur: sodium oxybate.Avoid taking MAO inhibitors (e.g., furazolidone, isocarboxazid, linezolid, moclobemide, phenelzine, procarbazine, rasagiline, selegiline, tranylcypromine) within 2 weeks before, during, and after treatment with this medication. In some cases a serious (possibly fatal) drug interaction may occur.If you are currently using any of these medications listed above, tell your doctor or pharmacist before starting this medication.Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially: tricyclic antidepressants (e.g., amitriptyline, nortriptyline), isoniazid, warfarin.Tell your doctor or pharmacist if you also take drugs that cause drowsiness such as: certain antihistamines (e.g., diphenhydramine), anti-seizure drugs (e.g., carbamazepine, phenytoin), medicine for sleep or anxiety (e.g., alprazolam, diazepam, zolpidem), muscle relaxants (e.g., cyclobenzaprine), narcotic pain relievers (e.g., codeine), psychiatric medicines (e.g., chlorpromazine, risperidone, trazodone).Check the labels on all your medicines (e.g., cough-and-cold products, diet aids) because they may contain drowsiness-causing ingredients or ingredients that could increase your heart rate or blood pressure. Ask your pharmacist about the safe use of those products.Acetaminophen is an ingredient in many nonprescription products and in some combination prescription medications. Read the labels carefully before taking other pain relievers, fever reducers, or cold products to see if they also contain acetaminophen. Consult your pharmacist if you are uncertain whether your other prescription or nonprescription products contain acetaminophen. (See also maximum daily dose information in Side Effects section.)This medication may interfere with certain laboratory tests (including certain urine glucose tests, urine catecholamine levels, urine 5-HIAA levels), possibly causing false test results. Make sure laboratory personnel and your doctors know you use this drug.This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
OVERDOSE: If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US national poison hotline at 1-800-222-1222. Canadian residents should call their local poison control center directly. Symptoms of overdose may include: restlessness, severe drowsiness/dizziness, low body temperature, fast/slow breathing, fast/slow/irregular heartbeat, unresponsiveness.
NOTES: Do not share this medication with others. It is against the law.Laboratory and/or medical tests (e.g., liver function tests) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.Certain foods/beverages or food additives (e.g., red wine, cheese, chocolate, monosodium glutamate, alcohol) as well as some lifestyle patterns (e.g., irregular eating/sleeping habits, stress) may bring about a migraine headache. Avoiding these "triggers" may help decrease the frequency of migraine headaches. Consult your doctor for more details.
MISSED DOSE: Not applicable.
STORAGE: Store at room temperature between 59-86 degrees F (15-30 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
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