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Roxee Medication Guide
Medication reference facts with explicit FDA-approval, off-label, source-limited, and safety context. Roxee does not sell, prescribe, or dispense medications.
Veterinary professional?
Roxee is still reviewing source support for this medication profile.
Roxee has safety or ingredient evidence for this medication, but a regulatory product/application match is still pending.
openFDA reaction terms and case summaries are supporting evidence, not proof of causality.
Drug type: Generic ingredient • Generic profile • Not FDA-approved for animals
Species: Both
Approval status: Not FDA-approved as an animal drug. No FDA-approved animal-drug application is linked for this record. It may represent extra-label, human-drug, bulk-compounding, export-only, or otherwise unapproved animal-use source data; use only under veterinarian direction.
Merged from the current Roxee medication system with field-level provenance, freshness, and completeness tracking.
Antihistamine sometimes used for allergies/itching and mild allergic reactions; may cause mild sedation. Species commonly shown: Both.
Antihistamine sometimes used for allergies/itching and mild allergic reactions; may cause mild sedation.
Oral
Store at room temperature.
Use caution with glaucoma, urinary retention, or certain cardiac conditions.
Sedation, dry mouth, GI upset; occasional paradoxical excitement.
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Used for:
Antihistamine sometimes used for allergies/itching and mild allergic reactions; may cause mild sedation.
Dosing note:
Exact dosing depends on your pet's species, weight, and health status. Use your veterinarian's instructions for the exact dose and schedule.
What to watch for:
When to call the vet:
What to tell or ask your vet today:
A source-aware map of what to know, what is uncertain, and what to verify with your veterinarian.
Roxee has limited cited overview evidence for Diphenhydramine; use the official documents and your veterinarian's instructions for product-specific decisions.
32 tracked reaction signals; 32 reported cases; 26 serious reports; 2 species groups. These are reporting and label-derived signals for interpretation with a veterinarian.
Adverse-event reports help form a watch list, but they do not prove the medication caused the reaction and they are not a risk ranking between medications.
Official labels, package inserts, and reviewed summaries carry more weight than isolated reports.
Case reports and openFDA terms are useful for pattern awareness, but they are incomplete, can include multiple exposures, and do not estimate an individual pet's probability of harm.
Unsteady walking (ataxia) (1 reports), Loss of appetite (1 reports), Hair loss (1 reports), Elevated globulins (1 reports), Elevated gamma-glutamyl transferase (1 reports)
Digestive (4), Skin & allergy (1), Neurologic (1), Behavior (3)
Dog (16 reports), Cat (16 reports)
Domestic Shorthair (1), ['Great Pyrenees', 'Retriever - Labrador'] (1), ['Terrier - Jack Russell', 'Terrier - Bull - American Pit'] (1), ['Retriever - Golden', 'Poodle - Standard'] (1). These are report metadata, not proof that a breed is at higher risk.
Verify whether Diphenhydramine fits the pet's species, current diagnosis, age, weight, organ status, pregnancy/lactation status, and concurrent medications.
Separate label-backed warnings from adverse-event reports and owner observations before changing the plan.
Use caution with glaucoma, urinary retention, or certain cardiac conditions, wobbly/unsteady walking, Loss of appetite, Hair loss
Repeated vomiting or diarrhea. Severe lethargy (hard to wake, very low energy). Collapse or fainting.
Review status / Updated / Sources
Review status: Clinical reviewer not listed
Updated: April 15, 2026, 10:04 AM UTC
Side effects to monitor:
Most reported reactions:
Emergency warning signs:
Source-backed clinical checkpoints for quick review.
Official label facts first, then secondary summaries. Marketing content is separated below.
Use caution with glaucoma, urinary retention, or certain cardiac conditions.
Snapshot first, detailed rows second. This section summarizes signal data and is not a diagnosis.
Filter stored openFDA reports by pet and report attributes. Counts describe reports in this data set, not risk.
Received 2025-12-23 · MSK · MSK
Received 2025-12-18 · MSK · MSK
Received 2025-12-16 · MSK · MSK
Received 2025-12-16 · MSK · MSK
Received 2025-12-15 · MSK · MSK
Received 2025-12-12 · MSK · MSK
Received 2025-12-12 · MSK · MSK
Received 2025-12-11 · MSK · MSK
Received 2025-12-10 · MSK · MSK
Received 2025-12-09 · MSK · MSK
Received 2025-12-01 · MSK · MSK
Received 2025-11-25 · MSK · MSK
Received 2025-11-20 · MSK · MSK
Received 2025-11-17 · MSK · MSK
Received 2025-11-13 · MSK · MSK
Received 2025-11-03 · MSK · MSK
Received 2025-10-27 · MSK · MSK
Received 2025-10-21 · MSK · MSK
Tap or hover a reaction to see what it means in plain language.
| Reaction | Body system | Cases | Species | Serious cases |
|---|---|---|---|---|
| Neurologic | 1 | Dog | 1 | |
| Digestive | 1 | Dog | 1 | |
| Skin & allergy | 1 | Dog | 1 | |
| Other | 1 | Cat | 1 | |
| Other | 1 | Cat | 1 | |
| Other | 1 | Cat | 1 | |
| Other | 1 | Cat | 1 | |
| Other | 1 | Dog | 1 |
Species coverage: Dog (16) Cat (16)
| Reaction | Body system | Species | Seriousness | Frequency | Reports |
|---|---|---|---|---|---|
| Neurologic | Dog | Serious | - | 1 | |
| Digestive | Dog | Serious | - | 1 | |
| Skin & allergy | Dog | Serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Other | Dog | Serious | - | 1 | |
| Other | Cat | Non-serious | - | 1 | |
| Other | Dog | Serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Digestive | Dog | Non-serious | - | 1 | |
| Other | Dog | Serious | - | 1 | |
| Digestive | Cat | Non-serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Other | Dog | Serious | - | 1 | |
| Other | Dog | Serious | - | 1 | |
| Other | Dog | Serious | - | 1 | |
| Other | Dog | Serious | - | 1 | |
| Other | Dog | Serious | - | 1 | |
| Other | Dog | Serious | - | 1 | |
| Digestive | Cat | Serious | - | 1 | |
| Behavior | Dog | Serious | - | 1 | |
| Behavior | Cat | Non-serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Other | Dog | Non-serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Behavior | Dog | Non-serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Other | Cat | Serious | - | 1 | |
| Other | Cat | Serious | - | 1 |
Store at room temperature.
The most useful source links appear first; full previews and metadata stay in the veterinary/professional layer.
Use original documents to confirm product-specific warnings, ingredients, and handling details with your veterinarian.
Full source previews and metadata remain in the veterinary/professional layer.
SPL · Structured Product Label
SPL · Structured Product Label
SPL · Structured Product Label
SPL · Structured Product Label
Canonical medication sections are above. This legacy block remains available for deeper cross-reference without cluttering the primary workflow.
Quick facts and links to official labeling and safety signals.
Diagnosis-code mappings are not available for this medication yet.
Global Pet owner/Vet mode is controlled in the header. This section avoids duplicate in-page persona tabs.
Normalized identifiers (NDC/NADA/ANADA) and package metadata from regulator listings.
| Package NDC | Product NDC | Form / Route | Status |
|---|---|---|---|
| 21091-695-01 | 21091 | - | |
| 43655-002-01 | 43655 | - | |
| 49427-329-45 | 49427 | - | |
| 49427-329-57 | 49427 | - | |
| 49427-330-45 | 49427 | - | |
| 49427-330-57 | 49427 | - | |
| 70782-200-08 | 70782 | - | |
| 70782-201-12 | 70782 | - | |
| 72087-021-10 | 72087 | - | |
| 72087-022-20 | 72087 | - | |
| 80547-116-50 | 80547 | - | |
| 80547-128-50 | 80547 | - |
Documents are tiered by source trust: Official, Clinical, Manufacturer, Marketing.
Every non-trivial field is expected to include provenance and update timestamps.
Antihistamine sometimes used for allergies/itching and mild allergic reactions; may cause mild sedation.
Use caution with glaucoma, urinary retention, or certain cardiac conditions.
Sedation, dry mouth, GI upset; occasional paradoxical excitement.
Source: FDA openFDA • Reference
De-duplicated reaction terms grouped by body system from FDA openFDA reports (not verified; does not prove causation).
Showing top 5 for Digestive.
Showing top 5 for Skin & allergy.
Showing top 5 for Neurologic.
Showing top 5 for Behavior.
Showing top 5 for Other.
Data source: FDA openFDA Animal & Veterinary adverse event reports.
These are individual FDA adverse event reports. They are unverified and do not prove the medication caused the reaction.
Cat, Domestic Shorthair, Male, 7 year, 8.618 kilogram • Drug: MSK, Unassigned, Oral, Frequency: 12 per hour • Reactions: Injection site hair loss, Reddening of the skin, Weight loss, Skin lesion NOS, Wound… • Outcome: Ongoing
Dog, ['Great Pyrenees', 'Retriever - Labrador'], Female, 31.661 kilogram • Drug: MSK, Unassigned, Unknown • Reactions: Vomiting • Outcome: Ongoing
Dog, ['Terrier - Jack Russell', 'Terrier - Bull - American Pit'], Female, 1 year, 17.236 kilogram • Drug: MSK, Unassigned, Unknown • Reactions: Vomiting, Hives, Reddening of the skin, Skin irritation, Urine leakage… • Outcome: Ongoing
Dog, ['Retriever - Golden', 'Poodle - Standard'], Male, 7 year, 43.273 kilogram • Drug: MSK, Unassigned, Unknown • Reactions: Thrombocytopenia, Blood loss NOS, Skin petechiae, Death • Outcome: Died
Dog, Terrier - Bull - American Pit, Male, 1 year, 33.339 kilogram • Drug: MSK, Tablet, Oral, Dose: 75 Milligram per animal • Reactions: Aggression • Outcome: Recovered/Normal
Dog, Terrier - Boston, Male, 9.75 year, 17.83 kilogram • Drug: MSK, Unassigned, Oral • Reactions: Proteinuria, Hypoalbuminaemia • Outcome: Ongoing
Dog, ['Bichon Frise', 'Chihuahua'], Female, 15 year, 3.493 kilogram • Drug: MSK, Unassigned, Unknown, Frequency: 12 per hour • Reactions: Seizure NOS, Unsteady walking (ataxia), Urinary incontinence • Outcome: Ongoing
Dog, Shih Tzu, Female, 11.68 year, 6.53 kilogram • Drug: MSK, Parenteral • Reactions: Not eating, Periorbital oedema, Fever, Local swelling, Nasal discharge… • Outcome: Ongoing
Data source: FDA openFDA Animal & Veterinary adverse event reports.
Overdose causes extreme drowsiness, tremors, seizures, or hyperexcitability. In severe cases, respiratory failure is possible. Treat with IV fluids, seizure control.
Store at room temperature.
Let others know your experience or advice regarding this medication.
This medication has not been reviewed by a veterinarian yet.