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(S)-Methoprene

Detailed information about (S)-Methoprene

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

Reviewed: Not available

Updated: February 12, 2026, 10:44 PM UTC

Sources:

Pet Owner Quick Guide

Start here first for the simple next-step summary.

Used for:

Your vet decides this. Here's what owners typically ask/watch for.

What to watch for:

  • Whining (1 reports)
  • Vomiting (1 reports)
  • Trembling (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:

  • Whining
  • Vomiting
  • Trembling

Most reported reactions:

  • Whining (1 reports)
  • Vomiting (1 reports)
  • Trembling (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, 10:44 PM UTC
  • 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 Feb 9, 2026, 3:14 AM UTC
  • openFDA case summaries: Source FDA openFDA | Refreshed Feb 9, 2026, 3:21 AM UTC
Image coming soon
(S)-Methoprene

(S)-Methoprene

Drug type: Generic ingredient • Generic profile • No FDA branded products linked

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

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
23
Reported cases
22
Serious reports
0
Species represented
1
Grouped by Body System
Digestive (2) · Vomiting, Decreased appetite Skin & allergy (3) · Itching, Hair loss, Erythema (for urticaria see Immune SOC) Neurologic (1) · Tiredness (lethargy) Behavior (1) · Behavioral disorder (unspecified) Effectiveness (1) · Lack of efficacy (ectoparasite) - flea Other (15) · Whining, Trembling, Staring
Most Reported Reactions
Reaction Body system Cases Species Serious cases
Other 1 Dog 0
Digestive 1 Dog 0
Other 1 Dog 0
Neurologic 1 Dog 0
Other 1 Dog 0
Other 1 Dog 0
Other 1 Dog 0
Other 1 Dog 0

Species coverage: Dog (23)

View detailed reaction table
Reaction Body system Species Seriousness Frequency Reports
Other Dog Non-serious - 1
Digestive Dog Non-serious - 1
Other Dog Non-serious - 1
Neurologic Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Effectiveness Dog Non-serious - 1
Skin & allergy Dog Non-serious - 1
Other Dog Non-serious - 1
Skin & allergy Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Other Dog Non-serious - 1
Digestive Dog Non-serious - 1
Other Dog Non-serious - 1
Behavior Dog Non-serious - 1
Skin & allergy Dog Unknown - -
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, 10:44 PM UTC
  • 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 Feb 9, 2026, 3:14 AM UTC
  • openFDA case summaries: Source FDA openFDA | Refreshed Feb 9, 2026, 3:21 AM UTC
Official (FDA)
Identity: Generic ingredient • No FDA branded products linked
No official FDA brand rows linked yet for this ingredient.
Case-reported brands (openFDA): MSK
Catalog species: Both
Safety (openFDA)
Top reactions: Dog 8 • Cat 0 • View
Case summaries: 4 (showing 4) • View
openFDA reports are unverified and do not prove causation.
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.

Top reaction signals
Whining (1) Vomiting (1) Trembling (1) Tiredness (lethargy) (1) Staring (1) Sleepiness - systemic disorder (1) Skin scab (1) Skin irritation (1)

Data Sources & Change Log

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

Official 1 Clinical 0 Manufacturer 0 Marketing 0
Current Field Facts
  • side_effects: Top reported reactions (openFDA): Alopecia, Behavioural disorder NOS, Crying, Decreased appetite, Discomfort NOS, Drug administration error. (Official, 2026-02-12)
Recent Revisions
  • side_effects updated 2026-02-12 22:44 by etl_backfill • Backfilled from existing medication fields

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) • Dog Decreased appetite (1) • Dog

Showing top 5 for Digestive.

Skin & allergy
Itching (1) • Dog Hair loss (1) • Dog

Showing top 5 for Skin & allergy.

Neurologic
Tiredness (1) • Dog

Showing top 5 for Neurologic.

Behavior
Behavioral disorder (1) • Dog

Showing top 5 for Behavior.

Effectiveness
Lack of efficacy (ectoparasite) - flea (1) • Dog

Showing top 5 for Effectiveness.

Other
Whining (1) • Dog Trembling (1) • Dog Staring (1) • Dog Sleepiness - systemic disorder (1) • Dog Skin scab (1) • Dog
Show more (10)
Skin irritation (1) • Dog Skin inflammation NOS (1) • Dog Skin haemorrhage NOS (1) • Dog Self trauma (1) • Dog Scratching (1) • Dog Inappropriate schedule of drug administration (1) • Dog Erythema (1) • Dog Drug administration error (1) • Dog Discomfort NOS (1) • Dog Crying (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, Chihuahua, Male, 6 year, 3.629 kilogram • Drug: MSK, Shampoo, Topical, Dose: 3 Other per animal • Reactions: Skin irritation, Scratching, Self trauma, Trembling, Tiredness (lethargy)… • Outcome: Outcome Unknown

  • Report ID: USA-USFDACVM-2025-US-023648
  • Serious AE: No
  • Treated For AE: No
  • Sex: Male
  • Age: 6.00 Year
  • Weight: 3.629 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Topical
  • Form: Shampoo
  • Dose: 3 Other per animal
Reactions Reported:
Skin irritation Scratching Self trauma Trembling Tiredness (lethargy) Erythema Skin inflammation NOS
Outcomes: Outcome Unknown

Dog, ['Shepherd Dog - German', 'Shepherd Dog - Belgian Malinois'], Female, 5.41 year, 29.937 kilogram • Drug: MSK, Unknown • Reactions: Vomiting • Outcome: Recovered/Normal

  • Report ID: USA-USFDACVM-2022-US-003115
  • Serious AE: No
  • Treated For AE: No
  • Sex: Female
  • Age: 5.41 Year
  • Weight: 29.937 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
Reactions Reported:
Vomiting
Outcomes: Recovered/Normal

Dog, ['Saluki', 'Terrier - Jack Russell'], Female, 11 year, 10.433 kilogram • Drug: MSK, Unknown • Reactions: Lack of efficacy (ectoparasite) - flea, Itching, Behavioral disorder (unspecified), Hair loss, Discomfort NOS… • Outcome: Outcome Unknown

  • Report ID: USA-USFDACVM-2022-US-000118
  • Serious AE: No
  • Treated For AE: Yes
  • Sex: Female
  • Age: 11.00 Year
  • Weight: 10.433 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Unknown
Reactions Reported:
Lack of efficacy (ectoparasite) - flea Itching Behavioral disorder (unspecified) Hair loss Discomfort NOS Skin scab Skin haemorrhage NOS Inappropriate schedule of drug administration
Outcomes: Outcome Unknown

Dog, Pit Bull, Male, 2 year, 27.215 kilogram • Drug: MSK, Topical • Reactions: Sleepiness - systemic disorder, Crying, Staring, Decreased appetite, Drug administration error… • Outcome: Outcome Unknown

  • Report ID: USA-USFDACVM-2021-US-059080
  • Serious AE: No
  • Treated For AE: No
  • Sex: Male
  • Age: 2.00 Year
  • Weight: 27.215 Kilogram
  • Case-reported brand: MSK
  • Case-reported manufacturer: MSK
  • Route: Topical
Reactions Reported:
Sleepiness - systemic disorder Crying Staring Decreased appetite Drug administration error Whining
Outcomes: Outcome Unknown

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

No approved storage guidance is linked yet for this ingredient. Use manufacturer packaging and veterinary guidance for handling/storage.

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