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Phenobarbital

Detailed information about Phenobarbital

Official label facts Owner quick guide first Marketing clearly labeled
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Reviewed / Updated / Sources

Reviewed: Not available

Updated: February 12, 2026, 7:40 PM UTC

Sources:

Pet Owner Quick Guide

Start here first for the simple next-step summary.

Used for:

Conditionally approved for the control of seizures associated with idiopathic epilepsy in dogs.

What to watch for:

  • Use caution with liver disease
  • Twitching (1 reports)
  • Tremors (1 reports)
  • very low energy (1 reports)

When to call the vet:

  • Repeated vomiting or diarrhea.
  • Severe lethargy (hard to wake, very low energy).
  • Collapse or fainting.
  • Trouble breathing.
  • Facial swelling or hives.
  • Blood in vomit or stool.

What to ask your vet today:

  • Is this medicine the right fit for my pet’s current symptoms?
  • Which warning signs mean I should call back right away?
  • How should I handle missed doses or refusal to take the medicine?
Safety & side effects

What to watch:

  • Use caution with liver disease
  • Twitching
  • Tremors
  • very low energy

Most reported reactions:

  • Twitching (1 reports)
  • Tremors (1 reports)
  • Tiredness (lethargy) (1 reports)

When to call your vet:

  • Repeated vomiting or diarrhea.
  • Severe lethargy (hard to wake, very low energy).
  • Collapse or fainting.
  • Trouble breathing.
Talk to a Vet / Find a Vet Near You Start Symptom Intake

Data freshness: source data appears current.

Latest refresh: Mar 21, 2026, 10:01 a.m.

Data freshness
  • Medication catalog: Source Roxee | Refreshed Feb 12, 2026, 7:40 PM UTC
  • Animal Drugs @ FDA: Source FDA | Refreshed Mar 21, 2026, 10:00 AM UTC
    Applications/products are imported from FDA export data.
  • Animal Drugs @ FDA previews: Source FDA | Refreshed Feb 9, 2026, 3:05 AM UTC
    Label highlights/doc links are fetched from FDA preview endpoints.
  • Animal Drug Product Listing Directory (NDC): Source FDA | Refreshed Mar 21, 2026, 10:01 AM UTC
    Package/product NDCs from FDA’s electronic listing directory (XLS).
  • openFDA reaction terms: Source FDA openFDA | Refreshed Mar 17, 2026, 10:02 AM UTC
  • openFDA case summaries: Source FDA openFDA | Refreshed Feb 9, 2026, 3:19 AM UTC
Image coming soon
Phenobarbital

Phenobarbital

Drug type: Generic ingredient • Branded profile • FDA branded products available

Species: Both

Manufacturer: Not available (source)

Quick Facts

Official label facts first, then secondary summaries. Marketing content is separated below.

Species: Both
Manufacturer: Not available
Form: Tablet
Identifiers:
NADA: 141578 NDC Package: 64950-541-01 NDC Package: 64950-541-10 NDC Package: 64950-542-01 NDC Package: 64950-542-10 NDC Package: 64950-543-01 NDC Package: 64950-543-10 NDC Package: 64950-544-01 NDC Package: 64950-544-10 NDC Package: 64950-560-01 NDC Package: 64950-560-10 NDC Package: 64950-561-01 NDC Package: 64950-561-10 NDC Package: 64950-562-01 NDC Package: 64950-562-10 NDC Package: 64950-563-01 NDC Package: 64950-563-10 NDC Product: 64950
Source metadata:

Warnings / Contraindications

Use caution with liver disease.

  • High: Use caution with liver disease.
Source metadata:

Adverse Reactions

Snapshot first, detailed rows second. This section summarizes signal data and is not a diagnosis.

Tap or hover a reaction to see what it means in plain language.

Tracked signals
32
Reported cases
32
Serious reports
13
Species represented
2
Grouped by Body System
Digestive (3) · Vomiting, Diarrhea, Blood in vomit Skin & allergy (1) · Twitching Neurologic (3) · Tremors, Tiredness (lethargy), Seizure NOS Effectiveness (2) · Partial lack of efficacy, Lack of efficacy - NOS Other (23) · Weight loss, Weight gain, Walking difficulty
Most Reported Reactions
Reaction Body system Cases Species Serious cases
Skin & allergy 1 Dog 1
Neurologic 1 Dog 1
Neurologic 1 Dog 1
Other 1 Dog 1
Neurologic 1 Cat 1
Other 1 Dog 1
Other 1 Cat 1
Effectiveness 1 Dog 1

Species coverage: Dog (17) Cat (15)

View detailed reaction table
Reaction Body system Species Seriousness Frequency Reports
Other Cat Non-serious - 1
Other Cat Non-serious - 1
Other Dog Non-serious - 1
Digestive Cat Non-serious - 1
Other Dog Non-serious - 1
Skin & allergy Dog Serious - 1
Neurologic Dog Serious - 1
Neurologic Dog Serious - 1
Other Cat Non-serious - 1
Other Dog Serious - 1
Neurologic Cat Serious - 1
Other Cat Non-serious - 1
Other Cat Non-serious - 1
Other Dog Non-serious - 1
Effectiveness Cat Non-serious - 1
Other Dog Serious - 1
Other Cat Serious - 1
Other Cat Non-serious - 1
Effectiveness Dog Serious - 1
Other Cat Serious - 1
Other Dog Serious - 1
Other Cat Serious - 1
Other Cat Non-serious - 1
Other Dog Non-serious - 1
Other Dog Serious - 1
Other Dog Non-serious - 1
Digestive Cat Serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Digestive Cat Non-serious - 1
Other Dog Non-serious - 1
Source metadata:

Storage & Handling

Store at room temperature; keep secured.

Documents

Owner handouts and official technical documents are grouped for faster access.

Owner handouts (0)
  • No owner handouts linked yet.
Official label / PI (0)
  • No official label or package insert links yet.
SPL (1)
  • FIDOQUEL™-CA1 · SPL
    https://animaldrugsatfda.fda.gov/adafda/app/search/public/spl/file/14694/FIDOQUEL%E2%84%A2-CA1
FOI (1)
Source metadata:
Veterinary reference (advanced)

Canonical medication sections are above. This legacy block remains available for deeper cross-reference without cluttering the primary workflow.

At a Glance

Quick facts and links to official labeling and safety signals.

Data freshness
  • Medication catalog: Source Roxee | Refreshed Feb 12, 2026, 7:40 PM UTC
  • Animal Drugs @ FDA: Source FDA | Refreshed Mar 21, 2026, 10:00 AM UTC
    Applications/products are imported from FDA export data.
  • Animal Drugs @ FDA previews: Source FDA | Refreshed Feb 9, 2026, 3:05 AM UTC
    Label highlights/doc links are fetched from FDA preview endpoints.
  • Animal Drug Product Listing Directory (NDC): Source FDA | Refreshed Mar 21, 2026, 10:01 AM UTC
    Package/product NDCs from FDA’s electronic listing directory (XLS).
  • openFDA reaction terms: Source FDA openFDA | Refreshed Mar 17, 2026, 10:02 AM UTC
  • openFDA case summaries: Source FDA openFDA | Refreshed Feb 9, 2026, 3:19 AM UTC
Official (FDA)
Identity: Generic ingredient • FDA branded products available
Official FDA brands: FIDOQUEL™-CA1
Case-reported brands (openFDA): MSK
Catalog species: Both • FDA-labeled species: Dog
Rx/OTC: RX
Form/route: Tablet • Oral
Applications: C 141-578
Documents: 1 (FOI: 1) • SPL: 1 • Label highlights • Official documents
Safety (openFDA)
Top reactions: Dog 19 • Cat 12 • View
Case summaries: 10 (showing 8) • View
openFDA reports are unverified and do not prove causation.
Explore
Related conditions: Seizures (idiopathic/structural)
Linked using: Fda_Label (0.95)
Diagnosis Codes

Diagnosis-code mappings are not available for this medication yet.

Counseling and Monitoring Highlights

Global Pet owner/Vet mode is controlled in the header. This section avoids duplicate in-page persona tabs.

Owner-facing counseling points
  • Use caution with liver disease. (Contraindication, High)
Top reaction signals
Twitching (1) Tremors (1) Tiredness (lethargy) (1) Systemic disorder NOS (1) Seizure NOS (1) Panting (1) Pancreatitis NOS (1) Lack of efficacy - NOS (1)

Identifiers & Packages

Normalized identifiers (NDC/NADA/ANADA) and package metadata from regulator listings.

Identifiers
NADA: 141578 NDC Package: 64950-541-01 NDC Package: 64950-541-10 NDC Package: 64950-542-01 NDC Package: 64950-542-10 NDC Package: 64950-543-01 NDC Package: 64950-543-10 NDC Package: 64950-544-01 NDC Package: 64950-544-10 NDC Package: 64950-560-01 NDC Package: 64950-560-10 NDC Package: 64950-561-01 NDC Package: 64950-561-10 NDC Package: 64950-562-01 NDC Package: 64950-562-10 NDC Package: 64950-563-01 NDC Package: 64950-563-10 NDC Product: 64950
Package NDC Product NDC Form / Route Status
64950-541-01 64950 -
64950-541-10 64950 -
64950-542-01 64950 -
64950-542-10 64950 -
64950-543-01 64950 -
64950-543-10 64950 -
64950-544-01 64950 -
64950-544-10 64950 -
64950-560-01 64950 -
64950-560-10 64950 -
64950-561-01 64950 -
64950-561-10 64950 -
64950-562-01 64950 -
64950-562-10 64950 -
64950-563-01 64950 -
64950-563-10 64950 -

Enriched Documents

Documents are tiered by source trust: Official, Clinical, Manufacturer, Marketing.

Data Sources & Change Log

Every non-trivial field is expected to include provenance and update timestamps.

Official 4 Clinical 1 Manufacturer 0 Marketing 0
Current Field Facts
  • storage_handling: Store at room temperature; keep secured. (Clinical, 2026-02-12)
  • contraindications: Use caution with liver disease. (Official, 2026-02-12)
  • side_effects: Sedation, increased thirst/urination, increased appetite. Long-term: liver enzyme changes. (Official, 2026-02-12)
  • usage: Anti-seizure medication used for epilepsy and seizure disorders. (Official, 2026-02-12)
Recent Revisions
  • side_effects updated 2026-02-12 19:40 by etl_backfill • Backfilled from existing medication fields
  • contraindications updated 2026-02-12 19:40 by etl_backfill • Backfilled from existing medication fields
  • usage updated 2026-02-12 19:40 by etl_backfill • Backfilled from existing medication fields

FDA Products & Applications (Animal Drugs @ FDA)

Official sponsor/proprietary-name/application-status records linked by active ingredient.

Product Sponsor Application Status Published
FIDOQUEL™-CA1
RX
Phenobarbital
Tablet • Oral
Label highlights
Official documents
Genus Lifesciences Inc. C 141-578 Approved Jun 3, 2024

Data source: FDA Animal Drugs @ FDA (public search export).

What It's For (FDA Label Highlights)

Extracted from FDA Animal Drugs @ FDA product labeling. Always confirm details with your veterinarian.

Species: Dog, No Use Class Stated Or Implied
Composition / specifications
15, 16.2, 30, 32.4, 60, 64.8, 97.2, or 100 mg per tablet
Dogs
Indication

Conditionally approved for the control of seizures associated with idiopathic epilepsy in dogs.

Dosage

Administer phenobarbital as tablets given orally twice a day at the minimum dosage of 2.5 mg per kilogram of body weight (mg/kg) and may be titrated to effect to a maximum dosage of 5 mg/kg. The dosage of phenobarbital tablets should be adjusted based on monitoring the clinical response of the individual patient.

Limitations

FDA page: Open in Animal Drugs @ FDA

Official Documents (FDA)

Direct links to FDA-hosted PDFs and SPL packages (when available).

Documents
SPL Packages

FDA page: Open in Animal Drugs @ FDA

Usage

Anti-seizure medication used for epilepsy and seizure disorders.

Source: FDA Animal Drugs @ FDA • Reference

Contraindications

Use caution with liver disease.

Side Effects

Sedation, increased thirst/urination, increased appetite. Long-term: liver enzyme changes.

Source: FDA openFDA • Reference

Top Reported Reactions (openFDA)

De-duplicated reaction terms grouped by body system from FDA openFDA reports (not verified; does not prove causation).

Digestive
Vomiting (1) • Cat Diarrhea (1) • Cat Blood in vomit (1) • Cat

Showing top 5 for Digestive.

Skin & allergy
Twitching (1) • Dog

Showing top 5 for Skin & allergy.

Neurologic
Tremors (1) • Dog Tiredness (1) • Dog Seizure NOS (1) • Cat

Showing top 5 for Neurologic.

Effectiveness
Partial lack of efficacy (1) • Cat Lack of efficacy - NOS (1) • Dog

Showing top 5 for Effectiveness.

Other
Weight loss (1) • Cat Weight gain (1) • Cat Walking difficulty (1) • Dog Unsteady gait (1) • Dog Tense abdomen (1) • Cat
Show more (18)
Systemic disorder NOS (1) • Dog Restlessness (1) • Cat Quiet (1) • Cat Product label issues (1) • Dog Panting (1) • Dog Pancreatitis NOS (1) • Cat Not eating (1) • Cat Ketosis (1) • Cat Intentional misuse (1) • Dog Inappetence (1) • Cat Hyperglycaemia (1) • Cat Gait abnormality (1) • Dog Fever (1) • Dog Elevated serum alkaline phosphatase (1) • Dog Decreased red blood cell count (1) • Dog Decreased haemoglobin (1) • Dog Decreased haematocrit (1) • Dog Anaemia NOS (1) • Dog

Showing top 5 for Other.

Data source: FDA openFDA Animal & Veterinary adverse event reports.

Adverse Event Case Summaries (openFDA)

These are individual FDA adverse event reports. They are unverified and do not prove the medication caused the reaction.

Dog, ['Weimaraner', 'Retriever - Labrador'], Male, 14 year, 26.3 kilogram • Drug: MSK, Unknown • Reactions: Gait abnormality, Walking difficulty, Unsteady gait, Product label issues • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-054553
  • Serious AE: No
  • Treated For AE: No
  • Sex: Male
  • Age: 14.00 Year
  • Weight: 26.300 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
Reactions Reported:
Gait abnormality Walking difficulty Unsteady gait Product label issues
Outcomes: Ongoing

Dog, Pekingese, Male, 11 year, 9.208 kilogram • Drug: MSK, Unassigned, Unknown • Reactions: Panting, Fever • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-055149
  • Serious AE: Yes
  • Treated For AE: Yes
  • Sex: Male
  • Age: 11.00 Year
  • Weight: 9.208 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
  • Form: Unassigned
Reactions Reported:
Panting Fever
Outcomes: Ongoing

Dog, Dachshund (unspecified), Female, 9 year, 7.711 kilogram • Drug: MSK, Oral, Dose: 1.50 tablet per 2 dose, Frequency: 1 per day • Reactions: Tremors, Tiredness (lethargy), Panting, Twitching, Systemic disorder NOS • Outcome: Recovered/Normal

  • Report ID: USA-USFDACVM-2025-US-055213
  • Serious AE: Yes
  • Treated For AE: Yes
  • Sex: Female
  • Age: 9.00 Year
  • Weight: 7.711 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Dose: 1.50 tablet per 2 dose
  • Frequency: 1 per day
Reactions Reported:
Tremors Tiredness (lethargy) Panting Twitching Systemic disorder NOS
Outcomes: Recovered/Normal

Dog, Bulldog - French, Male, 6 year, 16.5 kilogram • Drug: MSK, Unassigned, Oral • Reactions: Lack of efficacy - NOS, Intentional misuse • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-053288
  • Serious AE: Yes
  • Treated For AE: Yes
  • Sex: Male
  • Age: 6.00 Year
  • Weight: 16.500 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Unassigned
Reactions Reported:
Lack of efficacy - NOS Intentional misuse
Outcomes: Ongoing

Cat, Maine Coon, Male, 12 year, 11 kilogram • Drug: MSK, Tablet, Unknown • Reactions: Diarrhea, Inappetence, Ketosis, Seizure NOS, Pancreatitis NOS • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-050891
  • Serious AE: Yes
  • Treated For AE: No
  • Sex: Male
  • Age: 12.00 Year
  • Weight: 11.000 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
  • Form: Tablet
Reactions Reported:
Diarrhea Inappetence Ketosis Seizure NOS Pancreatitis NOS
Outcomes: Ongoing

Cat, ['Maine Coon', 'Cat (unknown)'], Male, 11.5 year, 6.6 kilogram • Drug: MSK, Unknown • Reactions: Weight loss, Ketosis • Outcome: Outcome Unknown

  • Report ID: USA-USFDACVM-2025-US-048528
  • Serious AE: No
  • Treated For AE: No
  • Sex: Male
  • Age: 11.50 Year
  • Weight: 6.600 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
Reactions Reported:
Weight loss Ketosis
Outcomes: Outcome Unknown

Cat, Domestic Longhair, Female, 6.4 kilogram • Drug: MSK, Unknown, Dose: 7.50 Milligram per animal, Frequency: 12 per hour • Reactions: Ketosis, Weight gain, Hyperglycaemia • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-048417
  • Serious AE: No
  • Treated For AE: No
  • Sex: Female
  • Weight: 6.400 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
  • Dose: 7.50 Milligram per animal
  • Frequency: 12 per hour
Reactions Reported:
Ketosis Weight gain Hyperglycaemia
Outcomes: Ongoing

Dog, Siberian Husky, Male, 11 year, 26.7 kilogram • Drug: MSK, Unknown • Reactions: Anaemia NOS, Decreased haematocrit, Decreased red blood cell count, Decreased haemoglobin, Elevated serum alkaline phosphatase • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-047727
  • Serious AE: No
  • Treated For AE: No
  • Sex: Male
  • Age: 11.00 Year
  • Weight: 26.700 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
Reactions Reported:
Anaemia NOS Decreased haematocrit Decreased red blood cell count Decreased haemoglobin Elevated serum alkaline phosphatase
Outcomes: Ongoing

Data source: FDA openFDA Animal & Veterinary adverse event reports.

Overdose Information

No approved overdose-management text is linked yet. If overdose is suspected, contact a veterinarian or emergency clinic immediately.

Storage & Handling

Store at room temperature; keep secured.

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