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Phenobarbital

PHENOBARBITAL ORAL SOLUTION, USP CIV

Approved
Approval ID

ee1fe3ac-7a2e-4133-90a2-1d8dc0552e74

Product Type

HUMAN PRESCRIPTION DRUG LABEL

Effective Date

Aug 29, 2023

Manufacturers
FDA

Bryant Ranch Prepack

DUNS: 171714327

Products 1

Detailed information about drug products covered under this FDA approval, including NDC codes, dosage forms, ingredients, and administration routes.

Phenobarbital

PRODUCT DETAILS

NDC Product Code72162-1268
Application NumberN/A
Marketing CategoryN/A
Route of AdministrationORAL
Effective DateAugust 29, 2023
Generic NamePhenobarbital

INGREDIENTS (7)

PHENOBARBITALActive
Quantity: 20 mg in 5 mL
Code: YQE403BP4D
Classification: ACTIB
ORANGEInactive
Code: 5EVU04N5QU
Classification: IACT
GLYCERINInactive
Code: PDC6A3C0OX
Classification: IACT
ALCOHOLInactive
Code: 3K9958V90M
Classification: IACT
FD&C RED NO. 40Inactive
Code: WZB9127XOA
Classification: IACT
WATERInactive
Code: 059QF0KO0R
Classification: IACT
SUCROSEInactive
Code: C151H8M554
Classification: IACT

Drug Labeling Information

WARNINGS SECTION

LOINC: 34071-1Updated: 9/15/2020

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 Barbiturates should be withdrawn gradually from any patient known to be taking excessive doses over long periods of time (see DRUG ABUSE AND DEPENDENCE).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 of chronic pain, because paradoxical excitement could be induced on 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.

DRUG ABUSE AND DEPENDENCE SECTION

LOINC: 42227-9Updated: 9/15/2020

DRUG ABUSE AND DEPENDENCE

Controlled Substance

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 to 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 or 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 withdrawal symptoms (hyperactivity, disturbed sleep, tremors, and hyperreflexia) are relieved, the dosage of Phenobarbital should be generally decreased and completely withdrawn over a 2-week period.

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Phenobarbital - FDA Drug Approval Details