Phenobarbital
Pronounced
"fee-no-BARB-ih-tall"
Common brand names:
Barbilixir Special
Uses
This medication is used alone or with other medications to control seizures. Controlling and reducing seizures lets you do more of your normal daily activities, reduces your risk of harm when you lose consciousness, and lessens your risk for a possibly life-threatening condition of frequent, repeated seizures. Phenobarbital belongs to a class of drugs known as barbiturate anticonvulsants/hypnotics. It works by controlling the abnormal electrical activity in the brain that occurs during a seizure. This medication is also used for a short time (usually no more than 2 weeks) to help calm you or help you sleep during periods of anxiety. It works by affecting certain parts of the brain to cause calming.
How to Use This Medication
Take this medication by mouth with or without food as directed by your doctor, usually once daily at bedtime for seizure control. Take with food or milk if stomach upset occurs. If you are using the liquid form of this medication, measure the dose carefully using a special measuring device/cup. Do not use a household spoon because you may not get the correct dose.
The dosage is based on your medical condition, phenobarbital blood levels, and response to treatment. Children's dosage may also be based on weight.
Your doctor may direct you to start this medication at a low dose and gradually increase your dose to prevent side effects such as drowsiness and dizziness. Follow your doctor's instructions carefully. Do not take more or less of this drug than prescribed.
It may take several weeks to reach the best dose for you and completely control your seizures. This medication works best when the amount of drug in your body is kept at a constant level. Take it at the same time(s) each day.
Do not stop taking this medication (and other anticonvulsant medications) without consulting your doctor. Your seizures may worsen or cause a very severe seizure that is difficult to treat (status epilepticus) when this drug is suddenly stopped.
If you suddenly stop using this medication, you may have withdrawal symptoms (such as anxiety, hallucinations, twitching, trouble sleeping). Withdrawal from phenobarbital can be severe and include seizures and (rarely) death. To help prevent withdrawal, your doctor may lower your dose slowly. Withdrawal is more likely if you have used phenobarbital for a long time or in high doses. Tell your doctor or pharmacist right away if you have withdrawal.
Though it helps many people, this medication may sometimes cause addiction. This risk may be higher if you have a substance use disorder (such as overuse of or addiction to drugs/alcohol). Take this medication exactly as prescribed to lower the risk of addiction. Ask your doctor or pharmacist for more details.
When this medication is used for a long time for anxiety or to help you sleep, it may not work as well. Phenobarbital should only be used for a short time for anxiety or sleep. Talk with your doctor if this medication stops working well.
Tell your doctor if your anxiety or seizure control worsens (such as the number of seizures increases).
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