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Phenobarbital Coupon - Phenobarbital 64.8mg tablet

phenobarbital

Generic Luminal
Used for Sedation, Epilepsy
Used for Sedation, Epilepsy

Phenobarbital treats seizures and is used as a sedative medication. It's a part of the barbiturate drug class. The most common side effect is sleepiness. It's a schedule IV controlled substance due to the risk of dependence. This means if you suddenly stop the medication, you could get withdrawal symptoms like weakness, muscle twitching, or even confusion and disorientation. There are no brand names available anymore, so only generic versions exist.

Reviewed by:
reviewer
Robert Chad Hakim, PharmD, BCCCP
reviewer
Kristianne Hannemann, PharmD
Last reviewed on July 24, 2023
BasicsWarningsSide effectsPros & consPharmacist tipsFAQsDosageInteractionsCostContraindicationsAlternativesLatest newsImagesReferencesPricesMedicare
Phenobarbital is a controlled substance, which means that it's more likely to be misused or cause dependence. There are federal and state laws that limit the amount of medication that can be prescribed or dispensed within a certain period of time.
basics-icon

What is Phenobarbital?

What is Phenobarbital used for?

How Phenobarbital works

Phenobarbital is a barbiturate. It works by slowing down brain activity. This is thought to help treat seizures.

Are you looking for information on Sezaby (phenobarbital) injection instead?

Drug Facts

Common BrandsLuminal (brand no longer available)
Drug ClassBarbiturate
Controlled Substance ClassificationSchedule IV
Generic StatusLower-cost generic available
AvailabilityPrescription only
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$49.43(save 86.02%)
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$6.91
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What are the risks and warnings for Phenobarbital?

Phenobarbital can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.

risk-warning

Dependence and withdrawal

  • Risk factors: History of substance use disorder | History of mental health problems | Using higher doses of phenobarbital for a long time | Stopping phenobarbital suddenly

    Phenobarbital carries a risk for dependence (when your body needs the medication to function normally). Take the medication exactly as prescribed. Don't change the dose or how often you take it without talking to your provider first. Misusing this medication can cause it to not work as well. It can also raise the risk for serious and possibly life-threatening side effects, such as dangerously slow breathing. If you need to stop taking phenobarbital, talk to your provider about a way to safely do so. Stopping the medication too suddenly can lead to life-threatening withdrawal symptoms, such as seizures and delirium.

    risk-warning

    Drowsiness

    • Risk factors: Taking high doses of phenobarbital | Drinking alcohol | Taking other medications that can cause sleepiness

      Phenobarbital can cause extreme dizziness and sleepiness, which can lower your ability to think, react, and focus. Your risk might be higher if you're taking other medications that can cause you to feel sleepy (e.g., benzodiazepines or sleep medications). Make sure you know how this medication affects you before driving a car or doing activities that require your concentration. Talk to your healthcare provider right away if you feel too sleepy from taking phenobarbital.

      risk-warning

      Extreme excitement

      • Risk factors: History of short-term or long-term pain | Older age | Younger age | Extreme weakness

        Phenobarbital can make certain people feel agitated, excited, or confused, rather than sleepy or calm, especially if you have short-term or long-term pain (e.g., cancer-related pain). Some older adults and children might also feel more excitement after taking the medication. Let your provider know if you experience this after taking phenobarbital.

        risk-warning

        Dangerously slow breathing (respiratory depression)

        • Risk factors: Taking medications that can cause slow breathing | Drinking alcohol | Older age | Medical conditions that cause breathing problems (e.g., COPD, asthma, head injury) | Taking too much phenobarbital

          Phenobarbital can cause dangerously slow breathing, which can be life-threatening. Don't take phenobarbital with alcohol or other medications that slow your body down (e.g., benzodiazepines, opioids, or muscle relaxants). Doing so raises your risk of extremely slowed breathing. If you or your loved one notices that you have trouble breathing or have bluish-colored lips, fingers, or toes, call 911 to get medical help right away.

          risk-warning

          Harm to newborn babies

          Phenobarbital can cause harm, including withdrawal symptoms like weakness or trouble sleeping, to babies when the medication is taken by pregnant mothers. Talk to your provider about the risks and benefits using phenobarbital while pregnant. There is a North American Antiepileptic Drug (NAAED) Pregnancy Registry to monitor the safety of anti-seizure medications during pregnancy. If you're currently pregnant and taking phenobarbital, it's encouraged that you enroll in the registry to help researchers learn more about the risks.

          Small amounts of phenobarbital can get into breast milk. This could lead to drowsiness in babies who are breastfed by mothers taking this medication. If you're breastfeeding, speak to your provider about safe ways to feed your baby.

          basics-icon

          What are the side effects of Phenobarbital?

          The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

          Common Side Effects

          Other Side Effects

          • Nausea
          • Vomiting
          • Constipation
          • Headache
          • Slowed heart rate
          • Fainting
          • Confusion

          Serious Side Effects

          Contact your healthcare provider immediately if you experience any of the following.
          • Dangerously slow breathing: shortness of breath, bluish-colored lips, fingers, or toes
          • Serious allergic and skin reactions: sore throat, fever, fatigue, rash, hives, painful blisters, skin reddening, skin peeling
          When do Phenobarbital possible side effects begin and end?
          Time passed since treatment started:
          HOURS
          DAYS
          WEEKS
          MONTHS
          Risk of sleepiness
          Risk of dizziness
          Risk of confusion
          If a line continues to the right, you'll likely keep experiencing this side effect once it starts.

          Source: DailyMed

          The following side effects have also been reported

          Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

          Check with your doctor immediately if any of the following side effects occur:

          Rare

          Confusion (especially in the elderly)

          dizziness, lightheadedness that continues, or fainting

          eye pain

          skin rash or hives

          Incidence not known

          Cough

          difficulty with swallowing

          fast irregular, pounding, or racing heartbeat or pulse

          fever

          hives or welts

          hoarseness

          irritation

          itching skin

          joint pain, stiffness, or swelling

          puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue

          redness of the skin

          shortness of breath

          skin rash

          tightness in the chest

          trouble with breathing

          wheezing

          Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

          More common

          Constipation

          decreased sweating

          dryness of the mouth, nose, throat, or skin

          Less common or rare

          Bloated feeling

          blurred vision

          difficult urination

          difficulty with swallowing

          drowsiness

          false sense of well-being

          headache

          increased sensitivity of eyes to light

          loss of memory

          nausea or vomiting

          redness or other signs of irritation at the place of injection

          trouble with sleeping

          unusual tiredness or weakness

          Incidence not known

          Decreased interest in sexual intercourse

          inability to have or keep an erection

          loss in sexual ability, desire, drive, or performance

          loss of taste

          For patients using scopolamine:

          After you stop using scopolamine, your body may need time to adjust. The length of time this takes depends on the amount of scopolamine you were using and how long you used it. During this period of time check with your doctor if you notice any of the following side effects:

          Anxiety

          irritability

          nightmares

          pupil of one eye is larger (patch only)

          sensitivity of eyes to light (patch only)

          trouble in sleeping

          Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

          Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

          pros-and-cons

          Pros and cons of Phenobarbital

          thumbs-up

          Pros

          Works to control seizures and as also as a sedative

          Dose can be adjusted based on your response

          Available in lower-cost, generic forms

          Available as a tablet and liquid

          thumbs-down

          Cons

          Can lead to withdrawal effects if stopped too suddenly

          Requires regular blood tests to check appropriate levels to determine the right dose

          Carries a risk of dependence

          Not safe during pregnancy

          pharmacist-tips

          Pharmacist tips for Phenobarbital

          pharmacist

          • You can take phenobarbital with or without food, but if it upsets your stomach, try taking it with food to help.

            • Make sure to mark your appointments in your calendar to see your provider and get any blood tests done while taking phenobarbital. Your provider will likely order different tests to make sure the medication is working well for you and you're not having side effects.

              • Phenobarbital can make you sleepy and dizzy. Don't drink alcohol, drive, or do anything that requires concentration until you know how this medication affects you.

                • Phenobarbital can interact with some commonly prescribed medications. Some medications that interact with include phenytoin (Dilantin), doxycycline, and warfarin (Coumadin). Make sure to tell your provider and pharmacist about all of the medications you're taking before starting phenobarbital.

                  • Phenobarbital can cause hormonal birth control to not work as well, which can lead to unwanted pregnancies. Talk to your provider about which methods of birth control would be the best option and if you need to use a back-up method of protection while taking phenobarbital.

                    • Don't change your dose or stop taking phenobarbital without talking to your provider first. Doing so can cause withdrawal symptoms like seizures, anxiety, and sleeping problems. Follow your provider's instructions to lower your dose slowly over a period of time to stop the medication completely.

                      Phenobarbital oral liquid

                      • Make sure to use an oral syringe or medication dosing cup to measure out your phenobarbital liquid dose. Don't use household spoons because they aren't accurate and might cause you to take the wrong dose. Be sure to shake the bottle well before measuring the dose.

                        • Store phenobarbital liquid at room temperature in the original bottle it came in from the pharmacy.

                          faqs

                          Frequently asked questions about Phenobarbital

                          Is phenobarbital a controlled substance?
                          Yes, phenobarbital is a schedule IV controlled substance. This is because it can be habit-forming with a risk of dependence. Dependence is when you rely on a medication to function normally and experience withdrawal symptoms (e.g., depression, weakness, vision changes) if you stop taking it suddenly. To help lower the risk for dependence, only take phenobarbital as prescribed by your provider. Follow your provider's instructions to slowly lower the dose before completely stopping the medication.
                          How long does phenobarbital stay in your system?
                          In adults, it takes on average about 16 days for most of phenobarbital to leave your body after a single dose. In children, it takes on average about 23 days. This time frame is estimated based on the half-life of phenobarbital. It can differ from person to person depending on other factors, such as your age and whether you have kidney or liver problems. If you're having side effects from phenobarbital, they might last up until the time it takes for the medication to clear out of your system.
                          What happens if you miss a dose of phenobarbital?
                          If you miss a dose of phenobarbital, it puts you at higher risk for seizures. Try to set a reminder of when to take your doses throughout the day. If you forget to take your dose, take it as soon as you remember. But if it's almost time for your next dose, skip the missed dose and continue with your usual dosing schedule. Never double up to make up for missed doses, since this can lead to serious side effects.
                          Is phenobarbital a narcotic?
                          No, phenobarbital isn't a narcotic because it's not an opioid pain medication. Phenobarbital is considered a barbiturate.
                          Does phenobarbital make you sleepy?
                          Yes, one of the most common side effects of phenobarbital is sleepiness. In fact, phenobarbital is used as a sedative to put people to sleep for surgeries or procedures. Before driving or performing activities where you need to be alert, wait and see how this medication affects you.
                          How long does phenobarbital take to work?
                          In general, phenobarbital starts to work within 1 hour and it typically lasts for 10 to 12 hours. But it can vary depending on your condition.
                          Can you drink alcohol while taking phenobarbital?
                          It's recommended that you avoid drinking alcohol while taking phenobarbital. Both alcohol and phenobarbital can make you feel sleepy and dizzy. So mixing alcohol with phenobarbital might make these effects worse. Also, alcohol can potentially make your seizures come back.
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                          dosage

                          Phenobarbital dosage forms

                          The average cost for 60 tablets of 64.8mg of Phenobarbital is $14.62 with a free GoodRx coupon. This is 70.43% off the average retail price of $49.43.
                          ml of elixir
                          Ml of elixir
                          DosageQuantityPrice as low asPrice per unit
                          20mg/5ml120 ml$6.91$0.06
                          tablet
                          Tablet
                          DosageQuantityPrice as low asPrice per unit
                          15mg60 tablets$7.68$0.13
                          16.2mg60 tablets$13.23$0.22
                          30mg60 tablets$9.59$0.16
                          32.4mg60 tablets$14.22$0.24
                          60mg60 tablets$10.24$0.17
                          64.8mg60 tablets$14.62$0.24
                          97.2mg60 tablets$15.41$0.26
                          100mg60 tablets$12.70$0.21

                          Typical dosing for Phenobarbital

                          The dose depends on your age, weight, and condition being treated. In general:

                          Sedation

                          • Adults: The typical dose is 30 mg to 120 mg by mouth per day, split up into 2 or 3 doses throughout the day. If used before a procedure, your provider might give you 100 mg to 200 mg by mouth once.

                          Seizures

                          • Adults: The typical dose is 60 mg to 200 mg by mouth per day.

                          • Children: The typical dose is 3 mg/kg to 6 mg/kg of body weight by mouth per day.

                          For seizures, your provider will adjust your dose based on blood levels of the medication. Your dose might differ if you're an older adult or have kidney or liver problems.

                          interactions

                          Interactions between Phenobarbital and other drugs

                          Phenobarbital may interact with certain medications or supplements. Always let your doctor and pharmacist know about any other medications or supplements (including prescribed and over-the-counter medications, vitamins, and dietary or herbal supplements) that you are currently taking. The list below does not include all possible drug interactions with Phenobarbital. Please note that only the generic name of each medication is listed below.

                          Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking any of these medicines, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

                          Using medicines in this class with any of the following medicines is not recommended. Your doctor may decide not to treat you with a medication in this class or change some of the other medicines you take.

                          Using medicines in this class with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

                          drug-cost

                          How much does Phenobarbital cost?

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                          Phenobarbital (generic)
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                          contraindications-icon

                          Phenobarbital contraindications

                          Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Phenobarbital will not be safe for you to take.
                          alternatives

                          What are alternatives to Phenobarbital?

                          There are a number of medications that your doctor can prescribe in place of Phenobarbital. Compare a few possible alternatives below.
                          Phenobarbital
                          Used for:
                          $6.91 Lowest GoodRx priceView Prices
                          Primidone (Mysoline)
                          Used for:

                          • Generalized tonic-clonic (grand mal) seizures

                          • Complex partial (psychomotor) seizures

                          • Partial (focal) seizures

                          $17.64 Lowest GoodRx priceView Prices
                          Phenytoin (Dilantin)
                          Used for:
                          $23.07 Lowest GoodRx priceView Prices
                          latest news

                          What is the latest news about Phenobarbital?

                          Read about eight phenobarbital interactions to be aware of and when to reach out to your healthcare professional for more information.

                          8 Phenobarbital Interactions to Watch for: Birth Control Pills, Blood Thinners, and More

                          Read about eight phenobarbital interactions to be aware of and when to reach out to your healthcare professional for more information.
                          Phenobarbital is an anticonvulsant medication used to treat epilepsy and seizures in dogs. Learn how phenobarbital works, how to give it to your dog, and more.

                          Phenobarbital for Dogs: Uses, Side Effects, And How It Works to Treat Seizures

                          Phenobarbital is an anticonvulsant medication used to treat epilepsy and seizures in dogs. Learn how phenobarbital works, how to give it to your dog, and more.
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                          Research suggests a potential interaction between folic acid and various anti-seizure (anti-epilepsy) medications. Does this interaction really happen? Learn more here.

                          Does Folic Acid Interact with Seizure Medications?

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                          Recently, Kerendia (finerenone) was FDA-approved for use in lowering the risk of kidney failure and heart-related death in adults with chronic kidney disease (CKD) as a result of type 2 diabetes. Created by Bayer, Kerendia is the first medication in its class approved for this use.

                          FDA Approves Kerendia for Chronic Kidney Disease in People With Diabetes

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                          images

                          Phenobarbital images

                          White Round 5013 V - Phenobarbital 64.8mg Tablet
                          This medicine is White, Round, Scored Tablet Imprinted With "5013 V".White Round 5013 V - Phenobarbital 64.8mg Tablet
                          White Round E5 112 - Phenobarbital 64.8mg Tablet
                          This medicine is White, Round, Scored Tablet Imprinted With "E5 112".White Round E5 112 - Phenobarbital 64.8mg Tablet
                          White Round 627 And Eci - Phenobarbital 64.8mg Tablet
                          This medicine is White, Round, Scored Tablet Imprinted With "Eci" And "627".White Round 627 And Eci - Phenobarbital 64.8mg Tablet
                          White Round 364 - Phenobarbital 64.8mg Tablet
                          This medicine is White, Round, Scored Tablet Imprinted With "364".White Round 364 - Phenobarbital 64.8mg Tablet
                          White Round 364 - Phenobarbital 64.8mg Tablet
                          This medicine is White, Round, Scored Tablet Imprinted With "364".White Round 364 - Phenobarbital 64.8mg Tablet
                          White Round T 32 - Phenobarbital 64.8mg Tablet
                          This medicine is White, Round, Scored Tablet Imprinted With "T 32".White Round T 32 - Phenobarbital 64.8mg Tablet
                          White Round W L And 141 - Phenobarbital 64.8mg Tablet
                          This medicine is White, Round, Scored Tablet Imprinted With "W L" And "141".White Round W L And 141 - Phenobarbital 64.8mg Tablet

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                          References

                          Best studies we found

                          Benzoni, T., et al. (2023). Procedural Sedation. StatPearls.

                          Centers for Disease Control and Prevention. (2020). Types of Seizures.

                          Drugs and Lactation Database (LactMed). (2023). Phenobarbital. National Institute of Child Health and Human Development.

                          View All References (6)

                          Lewis, C. B., et al. (2022). Phenobarbital. StatPearls.

                          Massachusetts General Hospital. (n.d.). The North American Antiepileptic Drug Pregnancy Registry.

                          MedlinePlus. (2020). Phenobarbital.

                          National Institute of Diabetes and Digestive and Kidney Diseases. (2020). Porphyria.

                          U.S. Department of Justice. (2020). Narcotics drug fact sheet.

                          Westminster Pharmaceuticals, LLC. (2023). PHENOBARBITAL tablet [package insert]. DailyMed.

                          GoodRx Health has strict sourcing policies and relies on primary sources such as medical organizations, governmental agencies, academic institutions, and peer-reviewed scientific journals. Learn more about how we ensure our content is accurate, thorough, and unbiased by reading our editorial guidelines.
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