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Cephalexin

Detailed information about Cephalexin

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:

For the treatment of secondary superficial bacterial pyoderma in dogs caused by susceptible strains of Staphylococcus pseudintermedius.

What to watch for:

  • Avoid in pets with known cephalosporin allergy
  • very low energy (1 reports)
  • Medication error NOS (1 reports)
  • Haematochezia (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:

  • Avoid in pets with known cephalosporin allergy
  • very low energy
  • Medication error NOS
  • Haematochezia

Most reported reactions:

  • Tiredness (lethargy) (1 reports)
  • Medication error NOS (1 reports)
  • Haematochezia (1 reports)

When to call your vet:

  • Repeated vomiting or diarrhea.
  • Severe lethargy (hard to wake, very low energy).
  • Collapse or fainting.
  • Trouble breathing.
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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 18, 2026, 10:03 AM UTC
  • openFDA case summaries: Source FDA openFDA | Refreshed Feb 9, 2026, 3:19 AM UTC
Image coming soon
Cephalexin

Cephalexin

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: Chewable Tablets
Identifiers:
NADA: 141326 NDC Package: 51311-026-10 NDC Package: 51311-036-10 NDC Package: 51311-046-10 NDC Package: 73309-179-01 NDC Package: 73377-243-01 NDC Product: 51311 NDC Product: 73309 NDC Product: 73377
Source metadata:

Warnings / Contraindications

Avoid in pets with known cephalosporin allergy.

  • High: Avoid in pets with known cephalosporin allergy.
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
11
Species represented
2
Grouped by Body System
Digestive (2) · Diarrhea, Decreased appetite Skin & allergy (4) · Itching, Head twitching, Hair loss at application site Neurologic (1) · Tiredness (lethargy) Behavior (1) · Behavioral disorder (unspecified) Effectiveness (1) · Lack of efficacy - NOS Other (23) · Medication error NOS, Lip smacking, Injection site tenderness
Most Reported Reactions
Reaction Body system Cases Species Serious cases
Neurologic 1 Cat 1
Other 1 Dog 1
Other 1 Cat 1
Other 1 Dog 1
Other 1 Cat 1
Other 1 Dog 1
Digestive 1 Cat 1
Digestive 1 Cat 1

Species coverage: Cat (24) Dog (8)

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

Storage & Handling

Store at room temperature.

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)
  • Rilexine® · SPL
    https://animaldrugsatfda.fda.gov/adafda/app/search/public/spl/file/2223/Rilexine%C2%AE
FOI (1)
  • UCM318614.pdf · FOI
    https://animaldrugsatfda.fda.gov/adafda/app/search/public/document/downloadFoi/883
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 18, 2026, 10:03 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: Rilexine®
Case-reported brands (openFDA): MSK
Catalog species: Both • FDA-labeled species: Dog
Rx/OTC: RX
Form/route: Chewable Tablets • Oral
Applications: NADA 141-326
Documents: 1 (FOI: 1) • SPL: 1 • Label highlights • Official documents
Safety (openFDA)
Top reactions: Dog 24 • Cat 13 • View
Case summaries: 10 (showing 8) • View
openFDA reports are unverified and do not prove causation.
Explore
Linked using: Fda_Label (0.95), 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
  • Avoid in pets with known cephalosporin allergy. (Contraindication, High)
Top reaction signals
Tiredness (lethargy) (1) Medication error NOS (1) Haematochezia (1) Glazed eye (1) Fever (1) Drinking a lot (1) Diarrhea (1) Decreased appetite (1)

Identifiers & Packages

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

Identifiers
NADA: 141326 NDC Package: 51311-026-10 NDC Package: 51311-036-10 NDC Package: 51311-046-10 NDC Package: 73309-179-01 NDC Package: 73377-243-01 NDC Product: 51311 NDC Product: 73309 NDC Product: 73377
Package NDC Product NDC Form / Route Status
51311-026-10 51311 -
51311-036-10 51311 -
51311-046-10 51311 -
73309-179-01 73309 -
73377-243-01 73377 -

Enriched Documents

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

  • UCM318614.pdf • FOI summary • Official • Feb. 22, 2024
    FDA FOI summary for application 141326

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. (Clinical, 2026-02-12)
  • contraindications: Avoid in pets with known cephalosporin allergy. (Official, 2026-02-12)
  • side_effects: GI upset, decreased appetite. (Official, 2026-02-12)
  • usage: Cephalosporin antibiotic used for susceptible bacterial infections (often skin/soft tissue). (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
Rilexine®
RX
Cephalexin
Chewable Tablets • Oral
Label highlights
Official documents
Virbac AH, Inc. NADA 141-326 Approved Feb 22, 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
Four tablet sizes containing 75 mg, 150 mg, 300 mg, or 600 mg of cephalexin.
Dogs
Indication
For the treatment of secondary superficial bacterial pyoderma in dogs caused by susceptible strains of Staphylococcus pseudintermedius.
Dosage
The recommended dose is 22 mg/kg (10 mg/lb) of body weight twice daily for 28 days.
Limitations
Federal law restricts this drug to use by or on the order of a licensed veterinarian. For Oral Use in Dogs Only.

FDA page: Open in Animal Drugs @ FDA

Official Documents (FDA)

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

Documents
  • Summary
    For the treatment of secondary superficial bacterial pyoderma in dogs caused by susceptible strains of Staphylococcus pseudintermedius.
SPL Packages

FDA page: Open in Animal Drugs @ FDA

Usage

Cephalosporin antibiotic used for susceptible bacterial infections (often skin/soft tissue).

Source: FDA Animal Drugs @ FDA • Reference

Contraindications

Avoid in pets with known cephalosporin allergy.

Side Effects

GI upset, decreased appetite.

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
Diarrhea (1) • Cat Decreased appetite (1) • Cat

Showing top 5 for Digestive.

Skin & allergy
Itching (1) • Cat Head twitching (1) • Dog Hair loss at application site (1) • Cat Facial swelling (possible allergy) (1) • Cat

Showing top 5 for Skin & allergy.

Neurologic
Tiredness (1) • Cat

Showing top 5 for Neurologic.

Behavior
Behavioral disorder (1) • Cat

Showing top 5 for Behavior.

Effectiveness
Lack of efficacy - NOS (1) • Cat

Showing top 5 for Effectiveness.

Other
Medication error NOS (1) • Dog Lip smacking (1) • Cat Injection site tenderness (1) • Dog Increased heart rate (1) • Cat Increased drinking (1) • Cat
Show more (18)
Inappetence (1) • Cat Hiding (1) • Cat Haematochezia (1) • Cat Glazed eye (1) • Dog Fever (1) • Cat Falling (1) • Cat Epidermal collarette (1) • Dog Dry mouth (1) • Cat Drowsiness - systemic disorder (1) • Cat Drinking a lot (1) • Dog Dilated pupils (1) • Cat Digestive tract stasis (1) • Cat Death by euthanasia (1) • Cat Death (1) • Cat Deafness (1) • Dog Dazed (1) • Cat Constipation (1) • Cat Abnormal movement 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, ['Terrier - Bull - American Pit', 'Dog (unknown)'], Female, 8 month, 32.205 kilogram • Drug: MSK, Unassigned, Oral • Reactions: Head twitching, Abnormal movement NOS, Injection site tenderness • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-055018
  • Serious AE: No
  • Treated For AE: No
  • Sex: Female
  • Age: 8.00 Month
  • Weight: 32.205 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Unassigned
Reactions Reported:
Head twitching Abnormal movement NOS Injection site tenderness
Outcomes: Ongoing

Dog, Shih Tzu, Male, 7.49 year, 8.61 kilogram • Drug: MSK, Unknown • Reactions: Not eating, Glazed eye, Not drinking, Weakness, Unclassifiable adverse event… • Outcome: Recovered/Normal

  • Report ID: USA-USFDACVM-2025-US-055776
  • Serious AE: Yes
  • Treated For AE: No
  • Sex: Male
  • Age: 7.49 Year
  • Weight: 8.610 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
Reactions Reported:
Not eating Glazed eye Not drinking Weakness Unclassifiable adverse event Drinking a lot
Outcomes: Recovered/Normal

Dog, ['Terrier - Bull - American Pit', 'Dog (unknown)'], Female, 5 year, 22.14 kilogram • Drug: MSK, Unassigned, Oral • Reactions: Epidermal collarette • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-055286
  • Serious AE: No
  • Treated For AE: No
  • Sex: Female
  • Age: 5.00 Year
  • Weight: 22.140 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Unassigned
Reactions Reported:
Epidermal collarette
Outcomes: Ongoing

Dog, Bulldog - English, Male, 5 year, 32.39 kilogram • Drug: MSK, Unassigned, Oral • Reactions: Lack of efficacy - NOS • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2025-US-055184
  • Serious AE: Yes
  • Treated For AE: Yes
  • Sex: Male
  • Age: 5.00 Year
  • Weight: 32.390 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Form: Unassigned
Reactions Reported:
Lack of efficacy - NOS
Outcomes: Ongoing

Dog, Pinscher - Miniature, Male, 12 year, 12.25 kilogram • Drug: MSK, Oral, Dose: 250 Milligram per animal, Frequency: 24 per hour • Reactions: Medication error NOS, Deafness • Outcome: Recovered with Sequela

  • Report ID: USA-USFDACVM-2025-US-054113
  • Serious AE: Yes
  • Treated For AE: No
  • Sex: Male
  • Age: 12.00 Year
  • Weight: 12.250 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
  • Dose: 250 Milligram per animal
  • Frequency: 24 per hour
Reactions Reported:
Medication error NOS Deafness
Outcomes: Recovered with Sequela

Cat, Cat (unknown), Mixed • Drug: MSK, Intravenous • Reactions: Death, Haematochezia, Decreased appetite, Regurgitation, Tiredness (lethargy)… • Outcome: Died, Euthanized, Outcome Unknown

  • Report ID: USA-USFDACVM-2025-US-052737
  • Serious AE: Yes
  • Treated For AE: No
  • Sex: Mixed
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Intravenous
Reactions Reported:
Death Haematochezia Decreased appetite Regurgitation Tiredness (lethargy) Diarrhea Death by euthanasia
Outcomes: Died, Euthanized, Outcome Unknown

Cat, Domestic Shorthair, Female, 11 year, 3.18 kilogram • Drug: MSK, Oral • Reactions: Diarrhea, Dilated pupils, Lack of efficacy - NOS, Constipation, Digestive tract stasis… • Outcome: Outcome Unknown

  • Report ID: USA-USFDACVM-2024-US-062942
  • Serious AE: No
  • Treated For AE: No
  • Sex: Female
  • Age: 11.00 Year
  • Weight: 3.180 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Oral
Reactions Reported:
Diarrhea Dilated pupils Lack of efficacy - NOS Constipation Digestive tract stasis Increased drinking Weakness Dazed Drowsiness - systemic disorder Hiding Falling Unable to stand Dry mouth
Outcomes: Outcome Unknown

Cat, Siamese, Male, 14 month, 5.443 kilogram • Drug: MSK, Unknown • Reactions: Tiredness (lethargy), Inappetence, Itching, Facial swelling (possible allergy), Lip smacking… • Outcome: Ongoing

  • Report ID: USA-USFDACVM-2024-US-058046
  • Serious AE: No
  • Treated For AE: No
  • Sex: Male
  • Age: 14.00 Month
  • Weight: 5.443 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
Reactions Reported:
Tiredness (lethargy) Inappetence Itching Facial swelling (possible allergy) Lip smacking Tremors Reddening of the skin
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.

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