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Phenytoin sodium and Phenobarbital oral

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.


(fen-ih-TOE-in WITH feen-oh-BARB-ih-tall)


This combination medication works to help control seizure disorders.

How To Use

Take this medication by mouth exactly as prescribed. Take this medication with a full glass (8 oz or 240 ml) of water unless your doctor directs you otherwise. Do not lie down for 30 minutes after taking this medication. For best effects, take this medication at evenly spaced times throughout the day and night. This will ensure a constant level of drug in your body. Do not take this more often or increase your dose without consulting your doctor. Do not stop taking this drug suddenly without your doctor's approval since seizures may reoccur. Your dose should be gradually reduced over time.

Side Effects

Headache, fatigue, drowsiness, dizziness, stomach upset and anxiety may occur the first several days as your body adjusts to the medication. If any of these effects continue or become bothersome, inform your doctor. Notify your doctor if you develop: rapid/pounding or irregular heartbeat, rash, confusion, incoordination, slurred speech, fever, flu-like symptoms, difficulty breathing, unusual bruising or bleeding, jaundice, seizures. This medication may cause drowsiness or dizziness. Use caution operating machinery or engaging in activities requiring alertness. It is important to maintain good oral hygiene by brushing and flossing your teeth regularly since this medication can cause gum disorders. If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor your medical history, especially of: kidney disease, blood disorders, liver disease, lung problems, diabetes, heart disease, thyroid disorder, any allergies. This medication is not recommended for use during pregnancy. Consult your doctor. This medication appears in breast milk. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of any over-the-counter or prescription medication you may take including: other medication for seizures, aspirin, acetaminophen, digoxin, steroids (e.g., prednisone), disulfiram, cyclosporine, "blood thinners" (e.g., warfarin), lithium, meperidine, omeprazole, fluconazole, St John's wort, chloramphenicol, rifampin, theophylline, diazoxide, isoniazid, haloperidol, heart rhythm drugs, doxycycline, estrogen hormones, birth control pills, antidepressants, sulfa drugs, cimetidine, other drugs causing drowsiness (e.g., antihistamines), diabetes medication, narcotic pain medicine (e.g., codeine). Avoid the use of alcoholic beverages while taking this medication as it can alter the drug's effects. This drug may interfere with the effectiveness of birth control pills. Discuss using other methods of birth control with your doctor. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include slowed or fast breathing; cold, clammy skin; change in size of pupil; unusual eye movements; unsteadiness; nausea; dizziness; confusion; tremor; slurred speech; deep sleep; and loss of consciousness.


Laboratory tests will be done periodically while taking this medication to monitor the effects and to prevent side effects. See your doctor regularly.

Missed Dose

Try to take each dose at the scheduled time. If you miss a dose, take it as soon as remembered; do not take it if it is near the time for the next dose, instead, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.


Store this medication at room temperature between 59 and 86 degrees F (15 to 30 degrees C) away from heat and light. Do not store in the bathroom. Discard capsules that become discolored. Keep this and all medications out of the reach of children.