HOW TO USE: Take this medication by mouth as directed by your doctor. If you are taking the immediate-release tablets or liquid form of this medication, take it usually 3 to 4 times a day or as directed by your doctor.If you are using the liquid, carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose.If you are taking the extended-release tablets, take them usually every 12 hours or as directed by your doctor. Do not crush or chew extended-release tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Also, do not split the tablets unless they have a score line and your doctor or pharmacist tells you to do so. Swallow the whole or split tablet without crushing or chewing.Antacids lower the absorption of this medication. If you are taking an antacid, take it at least 2 hours apart from this medication.The dosage is based on your medical condition and response to treatment. In children, the dosage is also based on weight.Do not increase your dose or take this drug more often without your doctor's approval. Your condition will not improve any faster and the risk of serious side effects may increase.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 anxiety, muscle twitching, shakiness, dizziness, worsening weakness, nausea, vomiting) may occur if you suddenly stop using this medication. Withdrawal from the phenobarbital can be severe and include seizures and (rarely) death. 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.When this medication is used for a long time, it may not work as well. Your doctor may need to increase your dose or change your medication. Talk with your doctor if this medication stops working well.Along with its benefits, this medication may rarely cause abnormal drug-seeking behavior (addiction). This risk may be increased if you have abused alcohol or drugs in the past. Take this medication exactly as prescribed to lessen the risk of addiction.Tell your doctor if your condition persists or worsens.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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