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PetDosageChart

Antiparasitic combination · For Dogs · 100 lb

How much Trifexis for a 100 lb dog?

A 100 lb dog (45.4 kg) should receive approximately 1360.5 mg of Trifexis per dose, given once monthly.

This dosage information is for educational purposes only. Always consult your veterinarian before giving any medication to your pet. Dosages may vary based on your pet's health conditions, other medications, and individual factors.

Content reviewed by licensed veterinarians. Sourced from Plumb's Veterinary Drug Handbook and the Merck Veterinary Manual.

Dosage · 100 lb dog

Trifexis dose for a 100 lb dog

Low Dose

1360.5

mg

Standard

1360.5

mg

Max Safe

2721.1

mg

Frequency

once monthly

Weight in kg

45.4 kg

Always confirm with your veterinarian before administering medication. These calculations are estimates based on published veterinary pharmacology references.

Other Weights

Trifexis for a different size dog

FAQ · 100 lb dog

Questions about Trifexis for a 100 lb dog

How much Trifexis for a 100 lb dog?
A 100 lb dog should receive approximately 1360.5 mg of Trifexis (Spinosad / Milbemycin Oxime) per dose, given once monthly. That works out to about 9.75 × 140 mg. Always confirm with your veterinarian before administering medication.
What is the safe dose range of Trifexis for a 100 lb dog?
The published dose range for a 100 lb dog is roughly 1360.5 mg (low) to 2721.1 mg (max safe), with 1360.5 mg as the typical standard dose. Frequency: once monthly.
How often can I give Trifexis to a 100 lb dog?
Trifexis is typically given once monthly. Do not exceed the recommended frequency without veterinary guidance.

Need a different weight?

Use the calculator on the main Trifexis page for any exact weight, or read the full dosage chart and safety information.

Full Trifexis dosage guide →

Sources · 09

Sources & references

The dosage information on this page is compiled from the following veterinary and pharmaceutical references:

  • Plumb's Veterinary Drug Handbook — the standard veterinary pharmacology reference used by veterinarians worldwide.
  • Merck Veterinary Manual — a trusted, peer-reviewed resource for veterinary professionals and pet owners.
  • DailyMed (FDA Drug Labels) — official FDA-approved drug labeling and prescribing information for Spinosad / Milbemycin Oxime.

Read more about our methodology and how we calculate dosages.