Phenobarbital Oral Solution 30 mg/7.5mL Solution — NDC 0121-1884-50 (Billing 00121-1884-50)
This is a package of Phenobarbital Oral Solution 30 mg/7.5mL Solution from PAI Holdings, LLC dba PAI Pharma, marketed since Aug 2021 and currently FDA-listed. It is this product's only package size.
Identity & classification
Regulatory identifiers FDA, NLM and CMS codes for this package
Drug-database identifiers Medi-Span GPI and First Databank GCN / HICL / AHFS classification
- GSN (GCN sequence number): 003586
- GCN: 12956
- GPI-14 (Medi-Span): 60100060001010
- HICL (First Databank): 001561
- AHFS class code: 28:12.04.00
- RxCUI (RxNorm): 702519
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 1, 2026
- FDA label on DailyMed · label index refreshed Oct 1, 2026
- RxNorm (NLM RxNav) · catalog refreshed Oct 1, 2026
- Medi-Span GPI (licensed)
- First Databank (licensed) · refreshed Oct 1, 2026
RxNorm drug class
This medicine belongs to the Barbiturates and derivatives class.
Where does this data come from?
- RxClass (NLM) · catalog refreshed Oct 1, 2026
Clinical
- It is used as a sedative and to control seizures. The tablets and oral solutions cover both. The injections have additional uses, such as short-term insomnia, sedation before surge...
- Please don't stop on your own. Phenobarbital can cause physical dependence, and stopping suddenly can lead to withdrawal problems like delirium and seizures. If you need to stop, y...
- No, this is a big one. Alcohol and other sedating drugs add to the drowsiness. Opioid pain medicines combined with phenobarbital can cause dangerously slow breathing, coma and deat...
- Is it safe to drink alcohol or take pain medicine with it?
Patient education
Supplement & herbal interactions
Where does this data come from?
- MedlinePlus (NLM) · refreshed Oct 1, 2026
- FDA label on DailyMed · label index refreshed Oct 1, 2026
Ask a licensed pharmacist directly — free, answered by our team.
Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per mL | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · Q2 2026 | $0.0923 | $34.61 / 375 ml |
Where does this data come from?
- CMS NADAC weekly file
- CMS ASP pricing files · refreshed Sep 20, 2026
- CMS Medicaid State Drug Utilization Data · refreshed Oct 2, 2026
- CMS Part D plan pricing files · refreshed Sep 24, 2026
- VA National Acquisition Center price file
Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Marketing end | Status |
|---|---|---|---|---|
| 00121-1884-50 You're viewing this Main listing | 5 TRAY in 1 CASE / 10 CUP, UNIT-DOSE in 1 TRAY / 7.5 mL in 1 CUP, UNIT-DOSE | 2021-08-20 | — | Active |
Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Phenobarbital Oral Solution 20 mg/5mL 00121-0942-16 | PAI | 473 ml | $0.047 | — | Availability likely | — |
| Phenobarbital 20 mg/5mL 13517-0207-16 | e5 | 473 ml | $0.047 | — | Discontinued | — |
| Phenobarbital 20 mg/5mL 13811-0299-08 | Trigen | 473 ml | $0.047 | — | Availability likely | — |
| Phenobarbital 20 mg/5mL 16571-0675-16 | Rising | 473 ml | $0.047 | — | Availability likely | — |
| Phenobarbital 20 mg/5mL 64380-0166-01 | Strides | 473 ml | $0.047 | — | Availability likely | — |
| Phenobarbital 20 mg/5mL 69367-0357-16 | Westminster | 473 ml | $0.047 | — | Availability likely | — |
| Phenobarbital 20 mg/5mL 69367-0367-16 | Westminster | 473 ml | $0.047 | — | Availability likely | — |
| Phenobarbital 20 mg/5mL 00121-0531-05 | Pharmaceutical | 10 cups | — | — | FDA listed | — |
| Phenobarbital Oral Solution 30 mg/7.5mLthis 00121-1884-50 | PAI | 10 cups | — | — | FDA listed | — |
| Phenobarbital Oral Solution 60 mg/15mL 00121-2826-50 | PAI | 10 cups | — | — | FDA listed | — |
| Phenobarbital Oral Solution 20 mg/5mL 54288-0163-47 | BPI | 473 ml | — | — | FDA listed | — |
| Phenobarbital 20 mg/5mL 60687-0671-67 | American | 10 cups | — | — | FDA listed | — |
| Phenobarbital 20 mg/5mL 62135-0962-22 | Chartwell | 10 cups | — | — | FDA listed | — |
| Phenobarbital 20 mg/5mL 63629-2399-01 | Bryant | 473 ml | — | — | FDA listed | — |
| Phenobarbital 20 mg/5mL 68999-0962-22 | Chartwell | 10 cups | — | — | FDA listed | — |
| Phenobarbital 20 mg/5mL 72162-1268-02 | Bryant | 473 ml | — | — | FDA listed | — |
| Phenobarbital Oral Solution 20 mg/5mL 81033-0163-54 | Kesin | 50 cups | — | — | FDA listed | — |
| Phenobarbital Oral Solution 20 mg/5mL 81033-0164-47 | Kesin | 473 ml | — | — | FDA listed | — |
| Phenobarbital Oral Solution 20 mg/5mL 82983-0417-47 | Ajenat | 473 ml | — | — | FDA listed | — |
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 1, 2026
- FDA Orange Book · refreshed Sep 3, 2026
- CMS NADAC weekly file
Availability & generic status
We did not find an FDA-approved generic match for this exact strength, form and route.
Where does this data come from?
- FDA Orange Book · refreshed Sep 3, 2026
What it looks like
Where does this data come from?
- FDA label on DailyMed · label index refreshed Oct 1, 2026
Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
Where does this data come from?
IACT rows and label-wide narrative are kept separate; availability and product-level specificity depend on the submitted label.- FDA label on DailyMed · label index refreshed Oct 1, 2026
- FDA openFDA NDC Directory · synced Oct 1, 2026
Inactive ingredient FAQ
Are inactive ingredients the same for every manufacturer?
Why might an inactive ingredient be missing?
Can inactive ingredients matter?
Manufacturer & labeler
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 1, 2026
- Drugs@FDA
Full prescribing information FDA SPL
🎯 Indications and Usage ▾
INDICATIONS USAGE A. Sedative B. Anticonvulsant - For the treatment of generalized and partial seizures.
⏱️ Dosage and Administration ▾
DOSAGE & ADMINISTRATION The dose of phenobarbital must be individualized with full knowledge of its particular characteristics. Factors of consideration are the patient’s age, weight, and condition. Sedation For sedation, the drug may be administered in single doses of 30 to 120 mg repeated at intervals; frequency will be determined by the patient’s response.
It is generally considered that no more than 400 mg of phenobarbital should be administered during a 24-hour period. Adults: Daytime Sedation: 30 to 120 mg daily in 2 to 3 divided doses. Oral Hypnotic: 100 to 200 mg.
Anticonvulsant Use Clinical laboratories reference values should be used to determine the therapeutic anticonvulsant level of phenobarbital in the serum. To achieve the blood levels considered therapeutic in pediatric patients, higher per-kilogram dosages are generally necessary for phenobarbital and most other anticonvulsants. In pediatric patients and infants, phenobarbital at a loading dose of 15 to 20 mg/kg produces blood levels of about 20 mcg/mL shortly after administration.
Phenobarbital has been used in the treatment and prophylaxis of febrile seizures. However, it has not been established that prevention of febrile seizures influences the subsequent development of epilepsy. Adults: 60 to 200 mg/day.
Pediatric Patients: 3 to 6 mg/kg/day. Special Patient Population Dosage should be reduced in the elderly or debilitated because these patients may be more sensitive to barbiturates. Dosage should be reduced for patients with impaired renal function or hepatic disease.
⛔ Contraindications ▾
CONTRAINDICATIONS Phenobarbital is contraindicated in patients who are hypersensitive to barbiturates, in patients with a history of manifest or latent porphyria, and in patients with marked impairment of liver function or respiratory disease in which dyspnea or obstruction is evident.
⚠️ Warnings ▾
WARNINGS 1. Habit Forming Phenobarbital may be habit forming. Tolerance and psychological and physical dependence may occur with continued use (see DRUG ABUSE AND DEPENDENCE and Pharmacokinetics under CLINICAL PHARMACOLOGY ).
Patients who have psychologic dependence on barbiturates may increase the dosage or decrease the dosage interval without consulting a physician and may subsequently develop a physical dependence on barbiturates. In order to minimize the possibility of overdosage or the development of dependence, the prescribing and dispensing of sedative-hypnotic barbiturates should be limited to the amount required for the interval until the next appointment. Abrupt cessation after prolonged use in a person who is dependent on the drug may result in withdrawal symptoms, including delirium, convulsions, and possibly death.
Barbiturates should be withdrawn gradually from any patient known to be taking excessive doses over long periods of time (see DRUG ABUSE AND DEPENDENCE ). 2. Acute or Chronic Pain Caution should be exercised when barbiturates are administered to patients with acute or chronic pain, because paradoxical excitement could be induced or important symptoms could be masked.
However, the use of barbiturates as sedatives in the postoperative surgical period and as adjuncts to cancer chemotherapy is well established. 3. Usage in Pregnancy Barbiturates can cause fetal damage when administered to a pregnant woman.
Retrospective, case-controlled studies have suggested a connection between the maternal consumption of barbiturates and a higher than expected incidence of fetal abnormalities. Barbiturates readily cross the placental barrier and are distributed throughout fetal tissues; the highest concentrations are found in the placenta, fetal liver, and brain. Fetal blood levels approach maternal blood levels following parenteral administration.
Withdrawal symptoms occur in infants born to women who receive barbiturates throughout the last trimester of pregnancy (see DRUG ABUSE AND DEPENDENCE ). If Phenobarbital is used during pregnancy or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the fetus. 4.
Usage in Children Phenobarbital has been reported to be associated with cognitive deficits in children taking it for complicated febrile seizures. 5. Synergistic Effects The concomitant use of alcohol or other CNS depressants may produce additive CNS depressant effects.
🤒 Adverse Reactions ▾
ADVERSE REACTIONS The following adverse reactions have been reported: CNS Depression - Residual sedation or “hangover”, drowsiness, lethargy, and vertigo. Emotional disturbances and phobias may be accentuated. In some persons, barbiturates such as phenobarbital repeatedly produce excitement rather than depression, and the patient may appear to be inebriated.
Irritability and hyperactivity can occur in children. Like other nonanalgesic hypnotic drugs, barbiturates such as phenobarbital, when given in the presence of pain, may cause restlessness, excitement, and even delirium. Rarely, the use of barbiturates results in the localized or diffuse myalgic, neuralgic, or arthritic pain, especially in psychoneurotic patients with insomnia.
The pain may appear in paroxysms, is most intense in the early morning hours, and is most frequently located in the region of the neck, shoulder girdle, and upper limbs. Symptoms may last for days after the drug is discontinued. Respiratory/Circulatory - Respiratory depression, apnea, circulatory collapse.
Allergic - Acquired hypersensitivity to barbiturates consists chiefly in allergic reactions that occur especially in persons who tend to have asthma, urticaria, angioedema, and similar conditions. Hypersensitivity reactions in this category include localized swelling, particularly of the eyelids, cheeks or lips, and erythematous dermatitis. Rarely exfoliative dermatitis (eg., Stevens-Johnson syndrome and toxic epidermal necrolysis) may be caused by phenobarbital and can prove fatal.
The skin eruption may be associated with fever, delirium, and marked degenerative changes in the liver and other parenchymatous organs. In a few cases, megaloblastic anemia has been associated with the chronic use of phenobarbital. Other - Nausea and vomiting; headache, osteomalacia.
The following adverse reactions and their incidence were compiled from surveillance of thousands of hospitalized patients who received barbiturates. Because such patients may be less aware of the milder adverse effects of barbiturates, the incidence of these reactions may be somewhat higher in fully ambulatory patients. More than 1 in 100 Patients The most common adverse reaction, estimated to occur at a rate of 1 to 3 patients per 100, is: Nervous System: Somnolence Less than 1 in 100 Patients Adverse reactions estimated to occur at a rate of less than 1 in 100 patients are listed below, grouped by organ system and by decreasing order of occurrence: Nervous System : Agitation, confusion, hyperkinesia, ataxia, CNS depression, nightmares, nervousness, psychiatric disturbances, hallucinations, insomnia, anxiety, dizziness, abnormality in thinking.
Respiratory System : Hypoventilation, apnea Cardiovascular System : Bradycardia, hypotension, syncope Digestive System : Nausea, vomiting, constipation Other Reported Reactions : Headache, injection site reactions, hypersensitivity reactions (angioedema, skin rashes, exfoliative dermatitis), fever, liver damage, megaloblastic anemia following chronic phenobarbital use. To report SUSPECTED ADVERSE REACTIONS, contact Pharmaceutical Associates, Inc. at 1-800-845-8210 or FDA at 1-800-FDA-1088 or www.fda.gov/wedwatch.
🆘 Overdosage ▾
OVERDOSAGE SECTION Signs and Symptoms The onset of symptoms following a toxic oral exposure to phenobarbital may not occur until several hours following ingestion. The toxic dose of barbiturates varies considerably. In general, an oral dose of 1 g of most barbiturates produces serious poisoning in an adult.
Death commonly occurs after 2 to 10 g of ingested barbiturate. The sedated, therapeutic blood levels of phenobarbital range between 5 to 40 mcg/mL; the usual lethal blood level ranges from 100 to 200 mcg/mL. Barbiturate intoxication may be confused with alcoholism, bromide intoxication, and various neurologic disorders.
Potential tolerance must be considered when evaluating significance of dose and plasma concentration. The manifestations of a long-acting barbiturate in overdose include nystagmus, ataxia, CNS depression, respiratory depression, hypothermia, and hypotension. Other findings may include absent or depressed reflexes and erythematous or hemorrhagic blisters (primarily at pressure points).
Following massive exposure to phenobarbital, pulmonary edema, circulatory collapse with loss of peripheral vascular tone, cardiac arrest, and death may occur. In extreme overdose, all electrical activity in the brain may cease, in which case a “flat” EEG normally equated with clinical death should not be accepted. This effect is fully reversible unless hypoxic damage occurs.
Consideration should be given to the possibility of barbiturate intoxication even in situations that appear to involve trauma. Complications such as pneumonia, pulmonary edema, cardiac arrhythmias, congestive heart failure, and renal failure may occur. Uremia may increase CNS sensitivity to barbiturates if renal function is impaired.
Differential diagnosis should include hypoglycemia, head trauma, cerebrovascular accidents, convulsive states and diabetic coma. Treatment To obtain up-to-date information about the treatment of overdose, a good resource is your certified Regional Poison Control Center. Telephone numbers of certified poison control centers are listed in the Physicians’ Desk Reference (PDR).
In managing overdosage, consider the possibility of multiple drug overdoses, interaction among drugs, and unusual drug kinetics in your patient. Protect the patient’s airway and support ventilation and perfusion. Meticulously monitor and maintain, within acceptable limits, the patient’s vital signs, blood gases, serum electrolytes, etc.
Absorption of drugs from the gastrointestinal tract may be decreased by giving activated charcoal, which, in many cases, is more effective than emesis or lavage; consider charcoal instead of or in addition to gastric emptying. Repeated doses of charcoal over time may hasten elimination of some drugs that have been absorbed. Safeguard the patient’s airway when employing gastric emptying or charcoal.
Alkalinization of urine hastens phenobarbital excretion, but dialysis and hemoperfusion are more effective and cause less troublesome alteration in electrolyte equilibrium. If the patient has chronically abused sedatives, withdrawal reactions may be manifest following acute overdose.
🧬 Clinical Pharmacology ▾
CLINICAL PHARMACOLOGY Barbiturates are capable of producing all levels of CNS mood alteration, from excitation to mild sedation, hypnosis, and deep coma. Overdosage can produce death. In high enough therapeutic doses, barbiturates induce anesthesia.
Barbiturates depress the sensory cortex, decrease motor activity, alter cerebellar function, and produce drowsiness, sedation, and hypnosis. Barbiturate-induced sleep differs from physiologic sleep. Sleep laboratory studies have demonstrated that barbiturates reduce the amount of time spent in the rapid eye movement (REM) phase of sleep or the dreaming stage.
Also, Stages III and IV sleep are decreased. Following abrupt cessation of barbiturates used regularly, patients may experience markedly increased dreaming, nightmares, and/or insomnia. Therefore, withdrawal of a single therapeutic dose over 5 or 6 days has been recommended to lessen the REM rebound and disturbed sleep that contribute to the drug withdrawal syndrome (for example, the dose should be decreased from 3 to 2 doses/day for 1 week).
In studies, secobarbital sodium and pentobarbital sodium have been found to lose most of their effectiveness for both inducing and maintaining sleep by the end of 2 weeks of continued drug administration even with the use of multiple doses. As with secobarbital sodium and pentobarbital sodium, other barbiturates (including amobarbital) might be expected to lose their effectiveness for inducing and maintaining sleep after about 2 weeks. The short-, intermediate-, and to a lesser degree, long-acting barbiturates have been widely prescribed for treating insomnia.
Although the clinical literature abounds with claims that the short-acting barbiturates are superior for producing sleep whereas the intermediate-acting compounds are more effective in maintaining sleep, controlled studies have failed to demonstrate these differential effects. Therefore, as sleep medications, the barbiturates are of limited value beyond short-term use. Barbiturates have little analgesic action at subanesthetic doses.
Rather, in subanesthetic doses, these drugs may increase the reaction to painful stimuli. All barbiturates exhibit anticonvulsant activity in anesthetic doses. However, of the drugs in this class, only phenobarbital, mephobarbital, and metharbital are effective as oral anticonvulsants in subhypnotic doses.
Barbiturates are respiratory depressants, and the degree of respiratory depression is dependent upon the dose. With hypnotic doses, respiratory depression produced by barbiturates is similar to that which occurs during physiologic sleep and is accompanied by a slight decrease in blood pressure and heart rate. Studies in laboratory animals have shown that barbiturates cause reductions in the tone and contractility of the uterus, ureters, and urinary bladder.
However, concentrations of the drugs required to produce this effect in humans are not reached with sedative-hypnotic doses. Barbiturates do not impair the normal hepatic function but have been shown to induce liver microsomal enzymes, thus increasing and/or altering the metabolism of barbiturates and other drugs (see Drug Interactions under PRECAUTIONS ). PHARMACOKINETICS Barbiturates are absorbed in varying degrees following oral or parenteral administration.
The salts are more rapidly absorbed than are the acids. The rate of absorption is increased if the sodium salt is ingested as a dilute solution or taken on an empty stomach. Duration of action, which is related to the rate at which the barbiturates are redistributed throughout the body, varies among persons and in the same person from time to time.
Phenobarbital is classified as a long-acting barbiturate when taken orally. Its onset of action is 1 hour or longer, and its duration of action ranges from 10 to 12 hours. Barbiturates are weak acids that are absorbed and rapidly distributed to all tissues and fluids, with high concentrations in the brain, liver, and kidneys.
Lipid solubility of t… [Excerpted — this section continues on DailyMed.]
📦 How Supplied / Storage and Handling ▾
NDC 0121-0942-16: 16 fl oz (473 mL) bottle. NDC 0121-0942-05: 5 mL unit dose cup. Case contains 50 unit-dose cups of 5 mL (NDC 0121-0942-50), packaged in 5 trays of 10 unit-dose cups each.
NDC 0121-1884-07: 7.5 mL unit dose cup. Case contains 50 unit-dose cups of 7.5 mL (NDC 0121-1884-50), packaged in 5 trays of 10 unit-dose cups each. NDC0121-2826-15: 15 mL unit dose cup.
Case contains 50 unit-dose cups of 15 mL (NDC 0121-2826-50), packaged in 5 trays of 10 unit-dose cups each. Contains alcohol, 14.25% Dispense in a tight, light-resistant container as defined in the USP/NF with a child resistant closure. Shake well before use.
Keep tightly closed. Store at 20° - 25°C (68° - 77°F). [see USP Controlled Room Temperature]. MANUFACTURED BY: Pharmaceutical Associates, Inc.
Greenville, SC 20605 www.paipharma.com R02/22
📋 Description ▾
DESCRIPTION The barbiturates are nonselective central nervous system (CNS) depressants that are primarily used as sedative-hypnotics. In subhypnotic doses, they are also used as anticonvulsants. The barbiturates and their sodium salts are subject to control under the Federal Controlled Substances Act.
Phenobarbital is a barbituric acid derivative and occurs as white, odorless, small crystals or crystalline powder that is very slightly soluble in water; soluble in alcohol, in ether, and in solutions of fixed alkali hydroxides and carbonates; sparingly soluble in chloroform. Phenobarbital is 5-ethyl-5-phenylbarbituric acid and has the empirical formula C12H12N2O3. Its molecular weight is 232.24.
It has the following structural formula: Phenobarbital is a substituted pyrimidine derivative in which the basic structure is barbituric acid, a substance that has no CNS activity. CNS activity is obtained by substituting alkyl, alkenyl, or aryl groups on the pyrimidine ring. Each 5 mL (teaspoon) contains 20 mg Phenobarbital and Alcohol 14.25%.
The oral solution also contains FD&C Red #40, glycerin, natural and artificial orange flavor, propylene glycol, benzyl alcohol, natural flavor, tocopherol, vegetable oil, purified water, and sucrose. image description
⚠️ Precautions ▾
PRECAUTIONS General Barbiturates may be habit forming. Tolerance and psychological and physical dependence may occur with continued use (see DRUG ABUSE AND DEPENDENCE ). Barbiturates should be administered with caution, if at all, to patients who are mentally depressed, have suicidal tendencies, or have a history of drug abuse.
Elderly or debilitated patients may react to barbiturates with marked excitement, depression, or confusion. In some persons, especially children, barbiturates repeatedly produce excitement rather than depression. In patients with hepatic damage, barbiturates should be administered with caution and initially in reduced doses.
Barbiturates should not be administered to patients showing the premonitory signs of hepatic coma. The systemic effects of exogenous and endogenous corticosteroids may be diminished by Phenobarbital. Thus, this product should be administered with caution to patients with borderline hypoadrenal function, regardless of whether it is of pituitary or of primary adrenal origin.
Information for Patients The following information and instructions should be given to patients receiving barbiturates. 1. The use of barbiturates carries with it an associated risk of psychological and/or physical dependence.
The patient should be warned against increasing the dose of the drug without consulting a physician. 2. Barbiturates may impair the mental and/or physical abilities required for the performance of potentially hazardous tasks, such as driving a car or operating machinery.
The patients should be cautioned accordingly. 3. Alcohol should not be consumed while taking barbiturates.
The concurrent use of the barbiturates with other CNS depressants (eg., alcohol, narcotics, tranquilizers, and antihistamines) may result in additional CNS-depressant effects. Laboratory Tests Prolonged therapy with barbiturates should be accompanied by periodic laboratory evaluation of organ systems, including hematopoietic, renal, and hepatic systems (see General under PRECAUTIONS and ADVERSE REACTIONS ). Drug Interactions Most reports of clinically significant drug interactions occurring with the barbiturates have involved phenobarbital.
However, the application of this data to other barbiturates appears valid and warrants serial blood level determinations of the relevant drugs when there are multiple therapies. 1. Anticoagulants Phenobarbital lowers the plasma levels of dicumarol and causes a decrease in anticoagulant activity as measured by the prothrombin time.
Barbiturates can induce hepatic microsomal enzymes resulting in increased metabolism and decreased anticoagulant response of oral anticoagulants (eg., warfarin, acenocoumarol, dicumarol, and phenprocoumon). Patients stabilized on anticoagulant therapy may require dosage adjustments if barbiturates are added to or withdrawn from their dosage regimen. 2.
Corticosteroids Barbiturates appear to enhance the metabolism of exogenous corticosteroids, probably through the induction of hepatic microsomal enzymes. Patients stabilized on corticosteroid therapy may require dosage adjustments if barbiturates are added to or withdrawn from their dosage regimen. 3.
Griseofulvin Phenobarbital appears to interfere with the absorptions of orally administered griseofulvin, thus decreasing its blood level. The effect of the resultant decreased blood levels of griseofulvin on therapeutic response has not been established. However, it would be preferable to avoid concomitant administration of these drugs.
4. Doxycycline Phenobarbital has been shown to shorten the half-life of doxycycline for as long as 2 weeks after barbiturate therapy is discontinued. This mechanism is probably through the induction of hepatic microsomal enzymes that metabolize the antibiotic.
If phenobarbital and doxycycline are administered concurrently, the clinical response to doxycycline should be monitored closely. 5. Phenytoin, Sodium Valproate, Valproic Acid The effect of barbiturates on the metabolism o… [Excerpted — this section continues on DailyMed.]
🧬 Pharmacokinetics ▾
PHARMACOKINETICS Barbiturates are absorbed in varying degrees following oral or parenteral administration. The salts are more rapidly absorbed than are the acids. The rate of absorption is increased if the sodium salt is ingested as a dilute solution or taken on an empty stomach.
Duration of action, which is related to the rate at which the barbiturates are redistributed throughout the body, varies among persons and in the same person from time to time. Phenobarbital is classified as a long-acting barbiturate when taken orally. Its onset of action is 1 hour or longer, and its duration of action ranges from 10 to 12 hours.
Barbiturates are weak acids that are absorbed and rapidly distributed to all tissues and fluids, with high concentrations in the brain, liver, and kidneys. Lipid solubility of the barbiturates is the dominant factor in their distribution within the body. The more lipid soluble the barbiturate, the more rapidly it penetrates all tissues of the body.
Barbiturates are bound to plasma and tissue proteins to a varying degree with the degree of binding increasing directly as a function of lipid solubility. Phenobarbital has the lowest lipid solubility, lowest plasma binding, lowest brain protein binding, the longest delay in onset of activity, and the longest duration of action. The plasma half-life for phenobarbital in adults ranges between 53 and 118 hours with a mean of 79 hours.
The plasma half-life for phenobarbital in children and newborns (less than 48 hours old) ranges between 60 to 180 hours with a mean of 110 hours. Barbiturates are metabolized primarily by the hepatic microsomal enzyme system, and the metabolic products are excreted in the urine, and, less commonly, in the feces. Approximately 25% to 50% of a dose of phenobarbital is eliminated unchanged in the urine.
The excretion of unmetabolized barbiturate is one feature that distinguishes the long-acting category from those belonging to other categories, which are almost entirely metabolized. The inactive metabolites of the barbiturates are excreted as conjugates of glucuronic acid.
🔒 Drug Abuse and Dependence ▾
DRUG ABUSE AND DEPENDENCE Phenobarbital is a Schedule IV drug. Dependence Barbiturates may be habit forming. Tolerance, psychological dependence, and physical dependence may occur, especially following prolonged use of high doses of barbiturates.
Daily administrations in excess of 400 mg of pentobarbital or secobarbital for approximately 90 days is likely to produce some degree of physical dependence. A dosage of 600 to 800 mg taken for at least 35 days is sufficient to produce withdrawal seizures. The average daily dose for the barbiturate addict is usually about 1.5 g.
As tolerance to barbiturates develops, the amount needed to maintain the same level of intoxication increases; tolerance to a fatal dosage, however, does not increase more than twofold. As this occurs, the margin between intoxicating dosage and fatal dosage becomes smaller. Symptoms of acute intoxication with barbiturates include unsteady gait, slurred speech, and sustained nystagmus.
Mental signs of chronic intoxication include confusion, poor judgment, irritability, insomnia, and somatic complaints. Symptoms of barbiturate dependence are similar to those of chronic alcoholism. If an individual appears to be intoxicated with alcohol to a degree that is radically disproportionate to the amount of alcohol in his or her blood, the use of barbiturates should be suspected.
The lethal dose of a barbiturate is far less if alcohol is also ingested. The symptoms of barbiturate withdrawal can be severe and may cause death. Minor withdrawal symptoms may appear 8 to 12 hours after the last dose of a barbiturate.
These symptoms usually appear in the following order: anxiety, muscle twitching, tremor of hands and fingers, progressive weakness, dizziness, distortion in visual perception, nausea, vomiting, insomnia, and orthostatic hypotension. Major withdrawal symptoms (convulsions and delirium) may occur within 16 hours and last up to 5 days after abrupt cessation of barbiturates. The intensity of withdrawal symptoms gradually declines over a period of approximately 15 days.
Individuals susceptible to barbiturate abuse and dependence include alcoholics and opiate abusers as well as other sedative-hypnotic and amphetamine abusers. Drug dependence on barbiturates arises from repeated administration of a barbiturate or agent with barbiturate-like effect on a continuous basis, generally in amounts exceeding therapeutic dose levels. The characteristics of drug dependence on barbiturates include: (a) a strong desire or need to continue taking the drug; (b) a tendency to increase the dose; (c) a psychic dependence on the effects of the drug related to subjective and individual appreciation of those effects; and (d) a physical dependence on the effects of the drug, requiring its presence for maintenance of homeostasis and resulting in a definite, characteristic and self-limited abstinence syndrome when the drug is withdrawn.
Treatment of barbiturate dependence consists of cautious and gradual withdrawal of the drug. Barbiturate-dependent patients can be withdrawn by using a number of different withdrawal regimens. In all cases, withdrawal requires an extended period of time.
One method involves substituting a 30-mg dose of phenobarbital for each 100- to 200-mg dose of barbiturate that the patient has been taking. The total daily amount of phenobarbital is then administered in 3 or 4 divided doses, not to exceed 600 mg daily. If signs of withdrawal occur on the first day of treatment, a loading dose of 100 to 200 mg of phenobarbital may be administered IM in addition to the oral dose.
After stabilization on phenobarbital, the total daily dose is decreased by 30 mg/day as long as withdrawal is proceeding smoothly. A modification of this regimen involves initiating treatment at the patient’s regular dosage level and decreasing the daily dosage by 10% if tolerated by the patient. Infants who are physically dependent on barbiturates may be given phenobarbital, 3 to 10 mg/kg/day.
After… [Excerpted — this section continues on DailyMed.]
📄 Package Label / Principal Display Panel ▾
PACKAGE LABEL.PRINCIPAL DISPLAY PANEL - One Pint (473 mL) NDC 0121-0942-16 Phenobarbital Oral Solution USP CIV 20 mg/5 mL Each 5 mL (teaspoonful) contains: Phenobarbital..............20 mg Alcohol.......................14.25% Inactive ingredients: FD&C Red #40, glycerin, natural and artificial orange flavor, propylene glycol, benzyl alcohol, natural flavor, tocopherol, vegetable oil, purified water, and sucrose. Rx ONLY One Pint (473 mL) Pharmaceutical Associates, Inc. Greenville, SC 20605 X0942160621 R06/21 PACKAGE LABEL.PRINCIPAL DISPLAY PANEL - One Pint (473 mL)
PACKAGE LABEL.PRINCIPAL DISPLAY PANEL - 5 mL Unit Dose Cup NDC 0121-0942-05 Phenobarbital Oral Solution USP CIV 20 mg/5 mL Alcohol 14.25% Package Not Child-Resistant Rx ONLY Pharmaceutical Associates, Inc. Greenville, SC 20605 PACKAGE LABEL.PRINCIPAL DISPLAY PANEL - 5 mL Unit Dose Cup
PACKAGE LABEL.PRINCIPAL DISPLAY PANEL - 7.5 mL Unit Dose Cup NDC 0121-1884-07 Phenobarbital Oral Solution USP CIV 30 mg/7.5 mL Alcohol 14.25% Package Not Child-Resistant Rx ONLY Pharmaceutical Associates, Inc. Greenville, SC 20605 PACKAGE LABEL.PRINCIPAL DISPLAY PANEL - 7.5 mL Unit Dose Cup
PACKAGE LABEL.PRINCIPAL DISPLAY PANEL - 15 mL Unit Dose Cup NDC 0121-2826-15 Phenobarbital Oral Solution USP CIV 60 mg/15 mL Alcohol 14.25% Package Not Child-Resistant Rx ONLY Pharmaceutical Associates, Inc. Greenville, SC 20605 PACKAGE LABEL.PRINCIPAL DISPLAY PANEL - 15 mL Unit Dose Cup
About this NDC listing & data coverage
Listed without an FDA application
This product's marketing category indicates it is marketed without an approved FDA application (no NDA, ANDA, or BLA on file). Having an NDC does not by itself establish FDA approval — the NDC Directory is a listing system, not an approval decision. Approval-linked data such as Orange Book therapeutic-equivalence ratings therefore does not apply.
What data is (and isn’t) available for this NDC — tap to expand
| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | ✓ Available |
| Inactive ingredients (structured) | — Not published for this NDC The labeler did not submit a structured excipient list, or no SPL is available. |
| NADAC pharmacy acquisition price (CMS) | — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey. |
| Orange Book / therapeutic-equivalence data | — Not published for this NDC Applies only to products approved under an NDA/ANDA; many listings are out of scope. |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |