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Roxee Medication Guide

S-Methoprene

Medication reference facts with explicit FDA-approval, off-label, source-limited, and safety context. Roxee does not sell, prescribe, or dispense medications.

Both Reference complete FDA data linked Non-Rx Capsule Wellmark International Official label facts Owner quick guide first
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Data freshness

Reference facts
Reference refreshed
Jun 22, 2026, 10:40 a.m.

These are the reference facts Roxee uses on browse cards and quick facts.

FDA applications
FDA application data refreshed
Jun 22, 2026, 10:40 a.m.

Sponsor, product, and application records imported from Animal Drugs @ FDA.

Safety reports
No safety reports linked
No refresh timestamp yet

openFDA reaction terms and case summaries are supporting evidence, not proof of causality.

Source timing details
Source timing details
  • Reference facts: Source Roxee | Refreshed Jun 22, 2026, 10:40 AM UTC
    The reference fact projection used for browse cards and quick facts.
  • Animal Drugs @ FDA: Source FDA | Refreshed Jun 22, 2026, 10:40 AM UTC
    Applications/products are imported from FDA export data.
  • Animal Drugs @ FDA previews: Source FDA | Refreshed Apr 11, 2026, 10:01 AM UTC
    Label highlights/doc links are fetched from FDA preview endpoints.
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S-Methoprene

S-Methoprene

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

Both Capsule Non-Rx 100% reference complete

Species: Both

Manufacturer: Wellmark International

Medication Snapshot

Merged from the current Roxee medication system with field-level provenance, freshness, and completeness tracking.

S-Methoprene

For oral use in dogs, 9 weeks of age and older and 4 pounds body weight or greater, for the prevention and control of flea populations. (S)-methoprene prevents and controls flea populations by preventing the development of flea eggs but does not kill adult fleas. Concurrent use of insecticides may be necessary for adequate control of adult fleas. Species commonly shown: Both, Dog And Puppy, Excluding Under 4 Weeks And 9 Pounds.

Generic name
S-Methoprene
Brand names
Zodiac® Fleatrol Flea Caps™ Hartz® Flea Control Capsules™
Manufacturer
Wellmark International
Species
Both, Dog And Puppy
Dosage forms
Capsule
Prescription
Non-prescription
Completeness
100%
Validation
Complete
Brand names
Zodiac® Fleatrol Flea Caps™ Hartz® Flea Control Capsules™
Dosage forms
Capsule

Indications / Uses

For oral use in dogs, 9 weeks of age and older and 4 pounds body weight or greater, for the prevention and control of flea populations. (S)-methoprene prevents and controls flea populations by preventing the development of flea eggs but does not kill adult fleas. Concurrent use of insecticides may be necessary for adequate control of adult fleas.

Side Effects

Top reported reactions (openFDA): Lack of efficacy (ectoparasite) - flea, Vomiting, Lethargy (see also Central nervous system depression in 'Neurological'), Seizure NOS, Diarrhoea, Lack of efficacy (ectoparasite) - tick NOS.

FAQ

Both, Dog And Puppy, Excluding Under 4 Weeks And 9 Pounds

No. Roxee does not currently show this as prescription-only.

Capsule

Related Conditions

Fleas (Flea Infestation)

Source Transparency

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Pet Owner Quick Guide

Start here first for the safest next-step summary before the deeper medication detail.

Used for:

For oral use in dogs, 9 weeks of age and older and 4 pounds body weight or greater, for the prevention and control of flea populations. (S)-methoprene prevents and controls flea populations by preventing the development...

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:

  • Unexplained death (1 reports)
  • Seizure NOS (1 reports)
  • Restlessness (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 tell or 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?

Next actions

Talk to a Vet / Find a Vet Near You Save to pet meds Share page Review report evidence
Research brief

Medication Research Insights

A source-aware map of what to know, what is uncertain, and what to verify with your veterinarian.

Source Backed Signals

What to know

Evidence-backed context Limited

Roxee has limited cited overview evidence for S-Methoprene; use the official documents and your veterinarian's instructions for product-specific decisions.

Source: openFDA case USA-USFDACVM-2025-US-069858
Safety signal coverage Reported signals

19 tracked reaction signals; 9 reported cases; 1 serious report; 2 species groups. These are reporting and label-derived signals for interpretation with a veterinarian.

Source: openFDA case USA-USFDACVM-2025-US-069858
Interpretation guardrail Not causation

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.

Evidence tension

Stronger signal Label / review

Official labels, package inserts, and reviewed summaries carry more weight than isolated reports.

Source: openFDA case USA-USFDACVM-2025-US-069858
Weaker signal Reported data

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.

Reaction signal map

Most reported reactions Top terms

Unexplained death (1 reports), Seizure NOS (1 reports), Restlessness (1 reports), Pica NOS (1 reports), Panting (1 reports)

Body systems represented Signal grouping

Digestive (2), Skin & allergy (2), Neurologic (1), Effectiveness (2)

Species and breed lens

Species represented in reports Species lens

Dog (11 reports), Cat (8 reports)

What your vet may verify

Fit for this patient Vet check

Verify whether S-Methoprene fits the pet's species, current diagnosis, age, weight, organ status, pregnancy/lactation status, and concurrent medications.

Evidence limitations Evidence review

Separate label-backed warnings from adverse-event reports and owner observations before changing the plan.

What to watch next

Watch list Owner-safe

Unexplained death, Seizure NOS, Restlessness

Call sooner if Escalation

Repeated vomiting or diarrhea. Severe lethargy (hard to wake, very low energy). Collapse or fainting.

Bottom line: Use this S-Methoprene brief as a structured watch list and source map, not as a reason to start, stop, or change treatment without your veterinarian.
Vet source depth
  1. openFDA case USA-USFDACVM-2025-US-069858 · adverse_reaction · adverse reactions
  2. FDA application profile · official_label · quick facts
  3. Medication usage source · fda_animal_drugs · quick facts
  4. FOI · document · documents
  5. SPL · document · documents
  6. SPL · document · documents

Evidence

Review status / Updated / Sources

Review status: Clinical reviewer not listed

Updated: April 22, 2026, 10:06 AM UTC

Sources:
Safety & side effects

Side effects to monitor:

  • Unexplained death
  • Seizure NOS
  • Restlessness

Most reported reactions:

  • Unexplained death (1 reports)
  • Seizure NOS (1 reports)
  • Restlessness (1 reports)

Emergency warning signs:

  • 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

Vet Fast Scan

Source-backed clinical checkpoints for quick review.

FDA-labeled species
Dog And Puppy
Indication / use
For oral use in dogs, 9 weeks of age and older and 4 pounds body weight or greater, for the prevention and control of flea populations. (S)-methoprene prevents and controls flea p…
Form / route / dose
Form: Capsule
Route: Oral
Confirm product label and patient-specific plan.
Warnings
No structured warnings linked yet.
Adverse-event caveat
No stored openFDA case explorer rows are linked yet.
Source docs

Quick Facts

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

Species: Both
Manufacturer: Wellmark International
Form: Capsule
Identifiers:
NADA: 141162
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
19
Reported cases
9
Serious reports
1
Species represented
2
Grouped by Body System
Digestive (2) · Drooling, Diarrhea Skin & allergy (2) · Hair loss at application site, Application site hair loss Neurologic (1) · Seizure NOS Effectiveness (2) · Lack of efficacy (ectoparasite) - flea, Lack of efficacy (bacteria) - NOS Other (12) · Unexplained death, Restlessness, Pica NOS
Most Reported Reactions
Reaction Body system Cases Species Serious cases
Other 1 Dog 1
Neurologic 1 Dog 0
Other 1 Dog 0
Other 1 Dog 0
Other 1 Dog 0
Effectiveness 1 Cat 0
Other 1 Dog 0
Other 1 Cat 0

Species coverage: Dog (11) Cat (8)

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

Source Documents

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.

Zodiac® Fleatrol Flea Caps™ SPL · SPL Hartz® Flea Control Capsules™ SPL · SPL ucm117227.pdf FOI · FOI

Full source previews and metadata remain in the veterinary/professional layer.

Owner handouts

0
No owner handouts linked yet.

Official label / PI

0
No official label or package insert links yet.

SPL

2

FOI

1

Zodiac® Fleatrol Flea Caps™

SPL · SPL

Open original
FDA Structured Product Label

Zodiac® Fleatrol Flea Caps™ Hartz® Flea Control Capsules™

Rendered from Roxee's cached FDA SPL package contents for on-page reading. Use Open original for the raw FDA ZIP/XML source.

Sponsor
Wellmark International
NADA
141-162
Status
OTC
Form
Capsule
Route
Oral
Species
Dog And Puppy
Composition / specifications
Each capsule contains 154, 308, or 462 milligrams (mg) of (S)-methoprene.

Dogs

Indication
For oral use in dogs, 9 weeks of age and older and 4 pounds body weight or greater, for the prevention and control of flea populations. (S)-methoprene prevents and controls flea populations by preventing the development of flea eggs but does not kill adult fleas. Concurrent use of insecticides may be necessary for adequate control of adult fleas.
Dosage
Capsules are given orally, once per week at the recommended minimum dosage of 10 mg of (S)-methoprene per pound of body weight (22 mg/kilograms).

Hartz® Flea Control Capsules™

SPL · SPL

Open original
FDA Structured Product Label

Zodiac® Fleatrol Flea Caps™ Hartz® Flea Control Capsules™

Rendered from Roxee's cached FDA SPL package contents for on-page reading. Use Open original for the raw FDA ZIP/XML source.

Sponsor
Wellmark International
NADA
141-162
Status
OTC
Form
Capsule
Route
Oral
Species
Dog And Puppy
Composition / specifications
Each capsule contains 154, 308, or 462 milligrams (mg) of (S)-methoprene.

Dogs

Indication
For oral use in dogs, 9 weeks of age and older and 4 pounds body weight or greater, for the prevention and control of flea populations. (S)-methoprene prevents and controls flea populations by preventing the development of flea eggs but does not kill adult fleas. Concurrent use of insecticides may be necessary for adequate control of adult fleas.
Dosage
Capsules are given orally, once per week at the recommended minimum dosage of 10 mg of (S)-methoprene per pound of body weight (22 mg/kilograms).

ucm117227.pdf

FOI · FOI

Open original
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
  • Reference facts: Source Roxee | Refreshed Jun 22, 2026, 10:40 AM UTC
    The reference fact projection used for browse cards and quick facts.
  • Animal Drugs @ FDA: Source FDA | Refreshed Jun 22, 2026, 10:40 AM UTC
    Applications/products are imported from FDA export data.
  • Animal Drugs @ FDA previews: Source FDA | Refreshed Apr 11, 2026, 10:01 AM UTC
    Label highlights/doc links are fetched from FDA preview endpoints.
Official (FDA)
Identity: Generic ingredient • No FDA branded products linked
No official FDA brand rows linked yet for this ingredient.
Catalog species: Both • FDA-labeled species: Dog And Puppy
Rx/OTC: OTC
Form/route: Capsule • Oral
Applications: NADA 141-162
Documents: 1 (FOI: 1) • SPL: 2 • Label highlights • Official documents
Safety (openFDA)
Top reactions: Dog 0 • Cat 0 • View
Case summaries: 0
openFDA reports are unverified and do not prove causation.
Explore
Related conditions: Fleas (Flea Infestation)
Linked using: Fda_Label (0.95)
Diagnosis Codes
ICD10_CM: B88.1
Tungiasis and other infestations

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
Unexplained death (1) Seizure NOS (1) Restlessness (1) Pica NOS (1) Panting (1) Lack of efficacy (ectoparasite) - flea (1) Increased heart rate (1) Inappropriate urination (1)

Identifiers & Packages

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

Identifiers
NADA: 141162

Enriched Documents

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

  • ucm117227.pdf • FOI summary • Official • June 1, 2016
    FDA FOI summary for application 141162

Data Sources & Change Log

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

Official 67 Clinical 4 Manufacturer 0 Marketing 0
Current Field Facts
  • side_effects: Top reported reactions (openFDA): Lack of efficacy (ectoparasite) - flea, Vomiting, Lethargy (see also Central nervous system depression in 'Neurological'), Se… (Clinical, 2026-05-02)
  • side_effects: Top reported reactions (openFDA): Lack of efficacy (ectoparasite) - flea, Vomiting, Lethargy (see also Central nervous system depression in 'Neurological'), Se… (Clinical, 2026-04-22)
  • side_effects: Top reported reactions (openFDA): Lack of efficacy (ectoparasite) - flea, Vomiting, Lethargy (see also Central nervous system depression in 'Neurological'), Se… (Clinical, 2026-04-15)
  • side_effects: Top reported reactions (openFDA): Lack of efficacy (ectoparasite) - flea, Vomiting, Lethargy (see also Central nervous system depression in 'Neurological'), Se… (Clinical, 2026-04-11)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-22)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-22)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-21)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-20)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-13)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-12)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-12)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-11)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-11)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-10)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-09)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-08)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-07)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-06)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-05)
  • indications: ZODIAC® FLEATROL™ FLEA CAPS™ and HARTZ® Flea Control Capsules™ are indicated for use in dogs, nine weeks of age and older and 4 pounds body weight or greater, … (Official, 2026-06-04)
Recent Revisions
  • side_effects updated 2026-05-02 10:05 by etl_backfill • Backfilled from existing medication fields
  • usage updated 2026-05-02 10:05 by etl_backfill • Backfilled from existing medication fields
  • side_effects updated 2026-04-30 10:09 by etl_backfill • Backfilled from existing medication fields
  • usage updated 2026-04-30 10:09 by etl_backfill • Backfilled from existing medication fields
  • side_effects updated 2026-04-22 10:07 by etl_backfill • Backfilled from existing medication fields
  • usage updated 2026-04-22 10:07 by etl_backfill • Backfilled from existing medication fields
  • side_effects updated 2026-04-15 10:04 by etl_backfill • Backfilled from existing medication fields
  • side_effects updated 2026-04-11 10:05 by etl_backfill • Backfilled from existing medication fields
  • side_effects updated 2026-02-12 22:44 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
Zodiac® Fleatrol Flea Caps™ Hartz® Flea Control Capsules™
OTC
(S) - methoprene
Capsule • Oral
Label highlights
Official documents
Wellmark International NADA 141-162 W Jun 1, 2016

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 And Puppy
Composition / specifications
Each capsule contains 154, 308, or 462 milligrams (mg) of (S)-methoprene.
Dogs
Indication
For oral use in dogs, 9 weeks of age and older and 4 pounds body weight or greater, for the prevention and control of flea populations. (S)-methoprene prevents and controls flea populations by preventing the development of flea eggs but does not kill adult fleas. Concurrent use of insecticides may be necessary for adequate control of adult fleas.
Dosage
Capsules are given orally, once per week at the recommended minimum dosage of 10 mg of (S)-methoprene per pound of body weight (22 mg/kilograms).
Limitations

FDA page: Open in Animal Drugs @ FDA

Usage

For oral use in dogs, 9 weeks of age and older and 4 pounds body weight or greater, for the prevention and control of flea populations. (S)-methoprene prevents and controls flea populations by preventing the development of flea eggs but does not kill adult fleas. Concurrent use of insecticides may be necessary for adequate control of adult fleas.

Source: FDA Animal Drugs @ FDA • Reference

Top Reported Reactions (openFDA)

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

Digestive
Drooling • Cat Diarrhea • Dog

Showing top 5 for Digestive.

Skin & allergy
Hair loss at application site • Cat Application site hair loss • Cat

Showing top 5 for Skin & allergy.

Neurologic
Seizure NOS (1) • Dog

Showing top 5 for Neurologic.

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

Showing top 5 for Effectiveness.

Other
Unexplained death (1) • Dog Restlessness (1) • Dog Pica NOS (1) • Dog Panting (1) • Dog Increased heart rate (1) • Dog
Show more (7)
Inappropriate urination (1) • Cat Agitation (1) • Dog Drunken gait • Dog Cough • Dog Application site scab • Cat Application site reddening • Cat Application site irritation • Cat

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.

No case-level openFDA reports are linked for this medication yet.

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.

Share Your Thoughts

Let others know your experience or advice regarding this medication.

This medication has not been reviewed by a veterinarian yet.