GENERIC NAME: BUTALBITAL/ACETAMINOPHEN - ORAL (bue-TAL-bi-tal/a-SEET-a-MIN-oh-fen)
BRAND NAME(S): Phrenilin
WARNING: One ingredient in this product is acetaminophen. Taking too much acetaminophen may cause serious (possibly fatal) liver disease. Adults should not take more than 4000 milligrams (4 grams) of acetaminophen a day. If you have liver problems, consult your doctor or pharmacist for a safe dosage of this medication. Daily use of alcohol, especially when combined with acetaminophen, may increase your risk for liver damage. Avoid alcohol. Check with your doctor or pharmacist for more information. Get medical help right away if you have any symptoms of liver damage, including: dark urine, persistent nausea/vomiting, stomach/abdominal pain, extreme tiredness, or yellowing eyes/skin.
Acetaminophen is an ingredient found in many nonprescription products and in some combination prescription medications (such as pain/fever drugs or cough-and-cold products). Carefully check the labels on all your medicines because they may also contain acetaminophen. Ask your pharmacist about using those products safely. Get medical help right away if you have taken more than 4000 milligrams of acetaminophen a day, even if you feel well.
USES: This combination medication is used to treat tension headaches. Acetaminophen helps to decrease the pain from the headache. Butalbital is a sedative that helps to decrease anxiety and cause sleepiness and relaxation.
HOW TO USE: See also Warning section.Take this medication by mouth with or without food, usually every 4 hours as needed or as directed by your doctor. Do not take more than 6 tablets in a 24-hour period.The dosage is based on your medical condition and response to therapy. This medication works best if it is used as the first signs of a headache occur. If you wait until the headache has worsened, the medication may not work as well.This medication may cause withdrawal reactions, especially if it has been used regularly for a long time or in high doses. In such cases, withdrawal symptoms (such as nausea/vomiting, mental/mood changes, 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 very unlikely, abnormal drug-seeking behavior (addiction) is possible with this medication. To lessen the risk of becoming addicted, do not increase your dose, take it more frequently, or take it for a longer time than prescribed. Properly stop the medication when so directed.Inform your doctor if you notice increased use of this medication, a worsening of headaches, an increase in the number of headaches, the medication not working as well, or use of this medication for more than 2 headache episodes a week. Do not take more than recommended. Your doctor may need to change your medication and/or add a separate medication to prevent the headaches.
SIDE EFFECTS: See also Warning section.Nausea, vomiting, abdominal pain, lightheadedness, dizziness, or drowsiness may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.To lower your risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.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: shortness of breath, mental/mood changes, fainting, seizure, fast heartbeat.Tell your doctor immediately if any of these rare but very serious side effects occur: signs of infection (e.g., fever, persistent sore throat), easy bruising/bleeding.A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: 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: See also Warning section.Before taking this medication, tell your doctor or pharmacist if you are allergic to acetaminophen or butalbital; or to other barbiturates (e.g., phenobarbital); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: severe breathing problems (e.g., bronchopneumonia), a certain enzyme disorder (porphyria).Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver disease, kidney disease, personal or family history of regular use/abuse of drugs/alcohol, mental/mood disorders, abdominal/intestinal problems.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. Avoid alcoholic beverages.Before having surgery, tell your doctor or dentist that you are using this medication.Older adults may be more sensitive to the side effects of this drug, especially drowsiness. This side effect can increase the risk of falling.During pregnancy, this medication should be used only when clearly needed. Using it for long periods or in high doses near the expected delivery date is not recommended because of possible harm to the unborn baby. Discuss the risks and benefits with your doctor. Infants born to mothers who have used this medication for an extended time may have withdrawal symptoms such as irritability, abnormal/persistent crying, vomiting, seizures, or diarrhea. Tell your doctor immediately if you notice any of these symptoms in your newborn.This drug passes into breast milk and could have undesirable effects on a nursing infant. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: See also Warning section.Your 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 medication because very serious interactions may occur: sodium oxybate.If you are currently using the medication listed above, tell your doctor or pharmacist before starting butalbital/acetaminophen.Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: anti-seizure drugs (e.g., carbamazepine, phenytoin), drugs affecting liver enzymes that remove this medication from your body (such as disulfiram, valproic acid, MAO inhibitors including isocarboxazid, linezolid, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, selegiline, tranylcypromine), isoniazid, methoxyflurane, phenothiazines (e.g., chlorpromazine).This drug can speed up the removal of other drugs from your body by affecting certain liver enzymes. These affected drugs include "blood thinners" (e.g., warfarin), cyclosporine, corticosteroids such as prednisone, estrogen, felodipine, metronidazole, quinidine, certain beta blockers such as metoprolol, theophylline, doxycycline.Tell your doctor or pharmacist if you also take drugs that cause drowsiness such as: certain antihistamines (e.g., diphenhydramine), medicine for sleep or anxiety (e.g., alprazolam, diazepam, zolpidem), muscle relaxants, narcotic pain relievers (e.g., codeine), psychiatric medicines (e.g., risperidone, amitriptyline, trazodone).Check the labels on all your medicines (e.g., cough-and-cold products) because they may contain drowsiness-causing ingredients. Ask your pharmacist about using those products safely.This medication may decrease the effectiveness of hormonal birth control such as pills, patch, or ring. This could cause pregnancy. Discuss with your doctor or pharmacist if you should use additional reliable birth control methods while using this medication. Also tell your doctor if you have any new spotting or breakthrough bleeding, because these may be signs that your birth control is not working well.This medication may interfere with certain laboratory tests (including urine 5-HIAA levels), possibly causing false test results. Make sure laboratory personnel and all 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 a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe drowsiness, slow breathing, severe dizziness, persistent nausea/vomiting, unusual sweating.
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NOTES: Do not share this medication with others.Massage, hot baths, and other relaxation methods can help with tension headaches. Consult your doctor or pharmacist for more details.Laboratory and/or medical tests (e.g., liver and kidney function tests) may be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
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.
Information last revised March 2013. Copyright(c) 2013 First Databank, Inc.
Related Disease Conditions
Tension Headache (Symptoms, Relief, Causes, Treatment)
A tension headache s one of the most common types of headaches, and the exact cause is not known. Factors that may contribute to tension or stress headaches are lack of sleep, increased stress (referred to as a stress headache), skipping meals, dehydration, medical diseases or conditions, anxiety, or changes at home, work, or school. Treatment of tension headaches include prescription and OTC medications, stress management, and treating any underlying illness or condition.
Treatment & Diagnosis
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Prevention & Wellness
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