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NexGard (Afoxolaner) Dose for Dogs: Strengths & Dose Calculator

Reviewed by Dr. Ravi Baraiya, B.V.Sc.Updated 2 Nov 20261 source

NexGard is a monthly afoxolaner chewable for fleas and ticks in dogs and puppies from 8 weeks of age and 4 lb, at a minimum of 2.5 mg/kg ^[1]. The chewable is chosen by weight band: 11.3, 28.3, 68 or 136 mg ^[1].

Contains: Afoxolaner
Company: Boehringer Ingelheim Animal Health
Forms: NexGard chewables
Label species: Dogs
Data from: USA (FDA label)
Type: Antiparasitic (fleas & ticks)

NexGard dose calculator

Results are calculated in your browser from the doses and strengths on this page. Check the strength printed on your pack and the label in your country before giving any dose.

NexGard strengths and presentations

Presentation	Contains	Strength check
NexGard chewables PO	Afoxolaner by weight band (below)^[1] 11.3, 28.3, 68 or 136 mg — by weight band.	Confirmed

NexGard chewables — by body weight
Body weight	Give
4–10 lb (1.8–4.5 kg)	NexGard 11.3 mg
10.1–24 lb (4.6–10.9 kg)	NexGard 28.3 mg
24.1–60 lb (10.9–27.2 kg)	NexGard 68 mg
60.1–121 lb (27.3–54.9 kg)	NexGard 136 mg
Over 121 lb: give the appropriate combination of chewables.

NexGard dose by species

Species	Use	Dose	Route	How often	Basis
Dogs	Fleas and ticks Minimum dose.	2.5 mg/kg^[1]	PO	Once a month	Label

Label directions

Give orally once a month at a minimum of 2.5 mg/kg, using the chewable for the dog's weight band ^[1].

Warnings and precautions

Isoxazolines have been linked to tremors, ataxia and seizures, even in dogs without a seizure history — use with caution in dogs with seizures or neurologic disorders ^[1].
Not evaluated in dogs under 8 weeks or under 4 lb ^[1].

About afoxolaner (the active ingredient)

Isoxazoline ectoparasiticide.

How it works

Afoxolaner binds to and inhibits insect and acarine ligand-gated chloride channels, especially GABA-gated ones; the resulting hyperexcitation kills fleas and ticks ^[1].

Key safety points

Isoxazolines have been associated with neurologic adverse reactions including tremors, ataxia and seizures — use with caution in dogs with a history of seizures ^[1].
Not evaluated in dogs under 8 weeks of age or under 4 lb ^[1].

All about afoxolaner — doses by species and every brand →

Frequently asked questions

Which NexGard size for my dog?

4–10 lb: 11.3 mg; 10.1–24 lb: 28.3 mg; 24.1–60 lb: 68 mg; 60.1–121 lb: 136 mg; over 121 lb: a combination of chewables ^[1].

How often is NexGard given?

Once a month ^[1].

More from Boehringer Ingelheim Animal Health

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NexGard is a trademark of its owner. This page is an independent clinical reference and is not affiliated with Boehringer Ingelheim Animal Health. Strengths, species and withdrawal periods can differ between countries — always follow the pack insert in your country.

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Medically reviewed by

Dr. Ravi Baraiya, B.V.Sc.

Veterinarian · Reviewed 2 Nov 2026

References

NEXGARD (afoxolaner) chewable — labelDailyMed (US NLM) — FDA-approved label, Boehringer Ingelheim · 2026 · Product label
Passage read from this source
NexGard® is given orally once a month, at the minimum dosage of 1.14 mg/lb (2.5 mg/kg).
Seizures have been reported in dogs receiving isoxazoline class drugs, even in dogs without a history of seizures.
in dogs and puppies 8 weeks of age and older, weighing 4 pounds of body weight or greater
This class has been associated with neurologic adverse reactions including tremors, ataxia, and seizures.

For veterinary professionals. Information supports — never replaces — clinical judgement; always check the current product label and local regulations.