What is this medicine?

PHENOBARBITAL (fee noe BAR bi tal) is a barbiturate. It may be used to help you sleep or may be used to help control seizures.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:

  • drug abuse or addiction
  • if you frequently drink alcohol containing drinks
  • kidney disease
  • liver disease
  • lung disease or breathing problems
  • porphyria
  • suicidal thoughts, plans, or attempt; a previous suicide attempt by you or a family member
  • an unusual or allergic reaction to phenobarbital, other barbiturates, other medicines, lactose, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth with a full glass of water. Follow the directions on the prescription label. Take your medicine at regular intervals. Do not take your medicine more often than directed. Do not stop taking except on your doctor's advice. If you have been taking this medicine regularly and suddenly stop taking it, you may increase the risk of seizures. Your doctor may gradually reduce the dose.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.

Patients over 65 years old may have a stronger reaction and need a smaller dose.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

Do not take this medicine with any of the following medications:

  • certain medicines used to treat HIV infection or AIDS that are given in combination with cobicistat

other barbiturates

  • primidone

voriconazole

This medicine may also interact with the following medications:

  • alcohol or medicines that contain alcohol

antihistamines

  • medicines for depression, anxiety, or psychotic disturbances

medicines for pain including pentazocine, buprenorphine, butorphanol, nalbuphine, tramadol, and propoxyphene

  • medicines for sleep

muscle relaxants

  • steroid medicines like prednisone or cortisone

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medicine?

Visit your doctor or health care provider for regular checks on your progress.

This medicine may cause serious skin reactions. They can happen weeks to months after starting the medicine. Contact your health care provider right away if you notice fevers or flu-like symptoms with a rash. The rash may be red or purple and then turn into blisters or peeling of the skin. Or, you might notice a red rash with swelling of the face, lips or lymph nodes in your neck or under your arms.

If you are taking this medicine for seizures, wear a medical identification bracelet or chain to say you have seizures, and carry a card that lists all your medications.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.

Birth control pills may not work properly while you are taking this medicine. Talk to your doctor about using an extra method of birth control.

The use of this medicine may increase the chance of suicidal thoughts or actions. Pay special attention to how you are responding while on this medicine. Any worsening of mood, or thoughts of suicide or dying should be reported to your health care provider right away.

Women who become pregnant while using this medicine may enroll in the North American Antiepileptic Drug Pregnancy Registry by calling 1-888-233-2334. This registry collects information about the safety of antiepileptic drug use during pregnancy.

This medicine may cause a decrease in vitamin D and folic acid. You should make sure that you get enough vitamins while you are taking this medicine. Discuss the foods you eat and the vitamins you take with your health care provider.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • breathing problems
  • fever, chills, or sore throat
  • rash, fever, and swollen lymph nodes
  • redness, blistering, peeling or loosening of the skin, including inside the mouth
  • unusual bleeding or bruising
  • unusually weak or tired
  • worsening of mood, thoughts or actions of suicide or dying
  • yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • dizziness
  • drowsiness
  • headache
  • irritability or nervousness
  • nausea

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medicine?

Keep out of the reach of children. This medicine can be abused. Keep your medicine in a safe place to protect it from theft. Do not share this medicine with anyone. Selling or giving away this medicine is dangerous and against the law.

This medicine may cause accidental overdose and death if taken by other adults, children, or pets. Mix any unused medicine with a substance like cat litter or coffee grounds. Then throw the medicine away in a sealed container like a sealed bag or a coffee can with a lid. Do not use the medicine after the expiration date.

Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Keep container tightly closed. Protect from light.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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