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Trifexis Tablets

  • 270mg/4.5mg » Pack of 6 Tablets £39.85
  • 425mg/7.1mg » Pack of 6 Tablets £41.27
  • 665mg/11.1mg » Pack of 6 Tablets £42.52
  • 1040mg/17.4mg » Pack of 6 Tablets £45.26
  • 1620mg/27mg » Pack of 6 Tablets £48.71

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£39.85 to £48.71


Trifexis Chewable Tablets contain two active ingredients (spinosad and milbemycine oxime). They are used to control fleas as well as roundworms and heartworms in dogs. One tablet will provide flea and heartworm control for up to 4 weeks. Fleas start dying within 30 minutes. It is usually best to treat the house/environment for fleas too if an outbreak has already occurred. It is not recommended to give Trifexis tablets for more than 6 months in one year, nor to animals under 3.9kg in weight or under 14 weeks of age.


Trifexis chewable tablets are mottled tan to brown, round, bi-convex tablets with a debossed code on one side and dimples on the other side.

Each tablet contains:


Milbemycin oxime

Trifexis 270mg / 4.5mg



Trifexis 425mg / 7.1mg



Trifexis 665mg / 11.1mg



Trifexis 1040mg / 17.4mg



Trifexis 1620mg / 27.0mg



The following list shows the debossed code and number of dimples marked on each strength of tablet:

Trifexis 270mg/4.5mg tablets: 4333 and 2 dimples

Trifexis 425mg/7.1mg tablets: 4346 and 3 dimples

Trifexis 665mg/11.1mg tablets: 4347 and no dimples

Trifexis 1040mg/17.4mg tablets: 4349 and 4 dimples

Trifexis 1620mg/27mg tablets: 4336 and 5 dimples


For the treatment and prevention of flea (Ctenocephalides felis) infestations in dogs when the concurrent prevention of heartworm (L3/L4 Dirofilaria immitis) disease and/or treatment of gastrointestinal nematode infections caused by hookworm (L4, immature adult L5 and adult Ancylostoma caninum). roundworms (immature adult L5, and adult Toxocara canis and adult Toxascaris leonina) or whipworm (adult Trichuris vulpis) is indicated.

The flea preventative effect against re-infestations is a result of the adulticidal activity and the reduction in egg production and persists for upto 4 weeks after administration.

Trifexis can be used as part of a treatment strategy for the control of Flea Allergy Dermatitis (FAD).

Dosage and administration

Trifexis tablets are administered orally in accordance with the following table to ensure a dose of 45-70 mg spinosad and 0.75-1.18 mg milbemycin oxime per kg bodyweight.

Tablets to be administered

Bodyweight of dog (kg)



3.9 - 6.0


1 x 270mg /4.5mg

6.1 - 9.4


1 x 425mg /7.1mg

9.5 - 14.7


1 x 665mg /11.1mg

14.8 - 23.1


1 x 1040 /17.4mg

23.2 - 36.0


1 x 1620mg /27mg

36.1 +

Use appropriate combination of tablets to ensure dose of 45-70mg spinosad / 0.75-1.18mg milbemycin oxime per kg bodyweight.

Trifexis tablets should be administered with food or immediately after feeding. The duration of efficacy may be reduced if administered on an empty stomach.

Spinosad starts killing fleas 30 minutes after adminstration , 100% of fleas are dead/moribund within 4 hours post-treatment.

If vomiting occurs within an hour of administration and the tablet is visible, re-dose the animal with another full dose to ensure maximum effectiveness of the product. It is recommended to observe treated dogs for 24-48 hours after dosing.

If a dose is missed, administer Trifexis with the next offering of food and resume a monthly dosing schedule ensuring not to use Trifexis for more than 6 consecutive months in any one year.

All dogs within the household should be treated. Cats in the household should be treated with a product authorised for use in that species.

For dogs living in non-heartworm endemic areas Trifexis can be used as part of the seasonal prevention of fleas in dogs with diagnosed concurrent gastrointestinal nematode infections. A single treatment is effective for gastrointestinal nematodes. After treatment of the nematode infection, further flea prevention should be continued with a monovalent product.

For dogs living in heartworm endemic areas

Prior to first administration of Trifexis, dogs in endemic areas or who have visited heartworm endemic areas must be tested for existing heartworm infection.

For the prevention of heartworm disease and the concurrent treatment and prevention of flea infestations, Trifexis must be given at regular monthly intervals during the time of the year when mosquitoes and fleas are present. Trifexis must be administered 1 month before the expected appearance of mosquitoes. It is recommended that heartworm prevention treatment should be continued at regular monthly intervals until at least 1 month after the last exposure to mosquitoes, but not for more than 6 consecutive months using Trifexis in any one year.

When Trifexis is used to replace another heartworm preventative product, the first dose of Trifexis must be given within a month of the last dose of the former medication.

Contra-indications, warnings, etc

Do not use in dogs under 14 weeks of age.

Do not use in case of known hypersensitivity to the active substances or to any of the excipients.

Special precautions for use in animals

Trifexis must not be given for more than 6 consecutive months in any one year.

Use with caution in dogs with pre-existing epilepsy. Accurate dosing is not possible in dogs weighing less than 3.9kg and therefore use in patients under these minimum weights is not recommended.

No studies have been performed in sick or convalescent dogs.

The safety of Trifexis in avermectin sensitive dogs/dogs with an MDR-1 mutation has not been sufficiently demonstrated. These dogs may be at higher risk for the development of adverse effects.

Use during pregnancy, lactation or lay

In laboratory studies (rats and rabbits) spinosad and milbemycin oxime have not produced any evidence of teratogenic, foetotoxic or maternotoxic effects nor any effect on the reproductive capacity in males and females. In pregnant and lactating dogs, the safety of Trifexis has not been sufficiently established. Trifexis tablets should only be used in pregnancy and lactation according to the risk/benefit assessment by the responsible veterinary surgeon.

As the safety of Trifexis in male dogs used for breeding has not been determined, it should only be used according to the benefit-risk assessment of the responsible veterinary surgeon.

Adverse Reactions (frequency and seriousness)

A commonly observed adverse reaction is vomiting, which occurs in the first 48 hours after dosing. In the majority of cases, vomiting was transient and mild and did not require symptomatic treatment.

At doses of 30 to 60 mg spinosad and 0.5 to 1mg milbemycin oxime per kg bodyweight, lethargy, anorexia/decreased appetite, diarrhoea, pruritus, dermatitis and reddening of the skin and pinna were commonly seen. Hypersalivation, muscle tremors, ataxia and seizures were uncommon. Post-marketing reports for spinosad indicate that in very rare cases, blindness, impaired vision and other eye disorders were observed.


The oral administration of spinosad and milbemycin oxime combination tablets at mean cumulative doses of up to 255mg spinosad and 4.2 mg milbemycin oxime per kg bodyweight (up to 3.6 times the maximum recommended dose) for 6 consecutive dosing periods in young dogs was well tolerated.

After spinosad administration, the incidence of vomiting on the day of, or the day after dosing has been observed to increase as a function of dose. Vomiting is most likely caused by a local effect on the small intestine. At doses in excess of the recommended dose, vomiting becomes a very commonly observed event.

Neurotoxicity characterised by transient mild depression, ataxia, trembling, mydriasis and excessive salivation has been observed in dogs given higher dose multiples of milbemycin oxime (5 to 10 mg/kg).

There is no antidote available. In the event of an overdose or adverse reaction, the animal may be given symptomatic treatment if deemed necessary.

For further information on other possible symptoms following overdose please refer to product SPC.


Spinosad and milbemycin oxime have been shown to be substrates for P-glycoprotein (P-gP) and therefore could interact with other P-gp substrates (for example digoxin, doxorubicin) or other macrocyclic lactones. Therefore concomitant treatment with other P-gp substrates or macrocyclic lactones could lead to enhanced toxicity.

Post marketing reports, following the concomitant use of spinosad with 'off label' high dose ivermectin indicate that dogs have experienced trembling/twitching, salivation/drooling, seizures, ataxia, mydriasis, blindness and disorientation.

Special precautions to be taken by the person administering Trifexis tablets to animals.

Accidental ingestion may cause adverse reactions. In the case of accidental ingestion, seek medical advise immediately and show the package leaflet or the label to the physician.

Keep out of the reach and sight of children.

Wash hands after administering Trifexis tablets.

Pharmaceutical precautions

For animal treatment only.

Keep the blister pack in the cardboard carton.

Any unused veterinary medicinal product, or waste material derived from the veterinary medicinal product should be disposed of in accordance with local requirements.

Legal category


Packaging Quantities

Blister packs (of 1, 3 or 6 chewable tablets) in a carton. The blister packs are formed from aluminium laminates, heat sealed with a PVC based coating (the product contact surface is PVC).

Not all pack sizes may be marketed.

Further information

Spinosad starts killing fleas 30 minutes after administration; 100% of fleas are dead/moribund within 4 hours post-treatment. Insecticidal activity against new infestations persists for up to 4 weeks. Spinosad comprises spinosyns A and D. The insecticidal activity of spinosad is characterised by nervous excitation, leading to muscle contractions and tremors, prostration, paralysis and rapid death of the flea. These effects are caused primarily by activation of nicotinic acetylcholine receptors (nAChRs). There is no known interaction at the binding site with other nicotinic or GABAergic receptors as spinosad acts through a novel insecticidal mechanism.

Milbemycin oxime is an antiparasitic endectocide belonging to the macrocyclic lactones. The activity of milbemycin oxime is related to its action on invertebrate neurotransmission.

In the case of a massive flea infestation, and at the beginning of control measures, the pet's local environment can be treated with a suitable insecticide and then vacuumed regularly. Fleas may be observed for a period of time after administration of Trifexis due to the emergence of adult fleas from pupae already present in the environment. Regular monthly treatments with spinosad breaks the fleas' life cycle and may be used to control the flea population in contaminated households.

Parasite resistance to any particular class of anthelmintic may develop following the frequent, repeated use of an anthelmintic of that class. Therefore, the use of Trifexis should be based on individual assessment and local epidemiological information about the current susceptibility of the target species in order to limit the possibility of a future selection for resistance.

Marketing authorisation number

EU/2/13/155/001 (1 tablet, 270mg/4.5mg).

EU/2/13/155/002 (1 x 3 tablets, 270mg/4.5mg).

EU/2/13/155/003 (1 x 6 tablets, 270mg/4.5mg).

EU/2/13/155/004 (1 tablet, 425mg/7.1mg).

EU/2/13/155/005 (1 x 3 tablets, 425mg/7.1mg).

EU/2/13/155/006 (1 x 6 tablets, 425mg/7.1mg).

EU/2/13/155/007 (1 tablet 665mg/11.1mg).

EU/2/13/155/008 (1 x 3 tablets, 665mg/11.1mg).

EU/2/13/155/009 (1 x 6 tablets, 665mg/11.1mg).

EU/2/13/155/010 (1 tablet, 1040mg/17.4mg).

EU/2/13/155/011 (1 x 3 tablets, 1040mg/17.4mg).

EU/2/13/155/012 (1 x 6 tablets, 1040mg/17.4mg).

EU/2/13/155/013 (1 tablet, 1620mg/27.0mg).

EU/2/13/155/014 (1 x 3 tablets, 1620mg/27.0mg).

EU/2/13/155/015 (1 x 6 tablets, 1620mg/27.0mg).

GTIN (Global Trade Item No)

Trifexis 270mg -GI


Trifexis 425mg -GI


Trifexis 665mg -GI


Trifexis 1040mg -GI


Trifexis 1620mg -GI


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