What Is Phenobarbital? | Epilepsy
What Is Phenobarbital (Luminal)?
Phenobarbital, known by the brand names Luminal and Solfoton, is a medication used to control seizures, treat anxiety and insomnia, and prevent withdrawal symptoms in patients who are addicted to certain barbiturate drugs.
Phenobarbital is in a class of medications called barbiturates, which work by slowing activity in the brain and depressing the central nervous system. It comes in tablet, liquid, and injectable forms.
Phenobarbital can be habit-forming. Don't discontinue it, take it more often, or take in larger doses without first talking with your doctor.
If you stop taking this medicine suddenly, you may experience symptoms such as anxiety, uncontrollable shaking, muscle twitching, dizziness, weakness, vision changes, vomiting, nausea, seizures, or difficulty falling and/or staying asleep.
Before taking phenobarbital, tell your doctor if you have ever had respiratory problems, including shortness of breath, lung disease, liver disease, kidney disease, adrenal gland abnormalities, or porphyria (conditions that result from a buildup of natural chemicals that produce porphyrin in your body).
Also tell your physician if you have ever consumed or regularly consume large amounts of alcohol, recreational drugs, or prescription drugs. You should also alert your doctor if you have ever had suicidal thoughts or depression.
Phenobarbital may decrease the effectiveness of hormonal contraceptives, such as birth control pills, patches, rings, injections, implants, or intrauterine devices (IUDs). Talk to your doctor about non-hormonal birth control options before taking phenobarbital.
Phenobarbital should not be used in children under 12 years old, as its safety and effectiveness has not been confirmed in this age group. This medicine should be used with caution in the elderly, due to increased sensitivity.
Pregnancy and Phenobarbital (Luminal)
Phenobarbital has been shown to harm a fetus. You should tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding before taking this medication.
Phenobarbital Side Effects
Call your doctor if you have any of the following side effects.
- Memory or concentration problems
- Excitement, irritability, aggression, or confusion
Serious Side Effects of Phenobarbital:
Call your doctor immediately if you experience any of the following.
- Fever or sore throat
- Slowed breathing or breathing difficulties
- Sores in the mouth
- Broken blood vessels under the skin
- Easy bruising or bleeding
- Swelling of the eyes, lips, or cheeks
- Blistering or peeling of the skin
- Restless muscle movements in the eyes, tongue, jaw, or neck
Phenobarbital and Alcohol
Don't drink alcohol while taking phenobarbital, as it may worsen the side effects of this medication.
Phenobarbital and Drug Interactions
Tell your doctor about all prescription, non-prescription, illegal, recreational, herbal, nutritional, or dietary drugs you take, especially:
Phenobarbital and Other Interactions
Phenobarbital may make you drowsy. Exercise caution when driving a car or operating machinery.
What Is the Typical Dosage for Phenobarbital?
Take this medication exactly as prescribed by your doctor by following the prescription labels. The following is a typical dosing schedule:
Adult oral dose:
As a daytime sedative: 30 to 120 milligrams (mg) in two to three divided doses
As a bedtime sleep aid: 100 to 320 mg
As an anticonvulsant: 50 to 100 mg, two to three times a day
Dosages should be reduced in elderly or ill patients because of increased sensitivity.
Take phenobarbital with a full glass of water. If you use it for insomnia, take it only at bedtime.
Signs of overdose may include:
- Loss of coordination
- Uncontrollable eye movements
- Slowed breathing
- Decrease in body temperature
Contact a poison control center or emergency room immediately if you suspect an overdose. You can get in touch with a poison control center at (800) 222-1222.
Missed Dose of Phenobarbital
If you miss a dose of phenobarbital, take it as soon as your remember. If it is almost time for your next dose, skip the missed dose and continue on your regular schedule. Don't "double up" to make up for a missed one.
By Julie Marks | Medically Reviewed by Mona Khanna, MD
Latest Update: 2014-11-05
Copyright © 2014 Everyday Health Media, LLC
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