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  • Active substances: Fenthion
  • Spot-on solution used against flea infestations in dogs
  • Target species: dogs
  • Administration: external
  • Package: 40 ml, 0.70 ml, 1.00 ml, 2.00 ml



1 ml contains:

Fenthion ………..…………………………..….  200 mg

Excipient: Isopropyl alcohol, Macrogol 200.



PET-SPOT C contains an organophosphorus compound with systemic action. Fenthion acts by inhibiting cholinesterase in synapses, paralyzing and killing parasites. It is used against flea infestations in dogs, being very efficient during the treatment and having a residual action for 4 weeks. In one hour after the treatment, Fenthion is absorbed in proportion of 50%, and after 8 hours 97% and it lays in the conjunctive tissue. It is eliminated from the organism in two days.

The long time effect is obtained by gradually eliminating the active substance from the deposits formed in the conjunctive tissue. The product’s efficiency is not affected by bathing the dog or by the fur’s length or condition.

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PET-SPOT C is used against flea infestations in dogs by applying a unique dose, directly on the skin. This provides protection for 3-4 weeks.



The treatment with PET-SPOT C consists in one application, directly on the skin.

Application method: Take out the tube from the package and toggle it vertically, avoiding face contact. Remove the cover by unscrewing. Separate the fur between scapulas until you see the skin. Apply all the solution by pipetting directly on the skin, holding the pipette tube upright on the neck.

Doses: In case there are no other prescriptions the treatment will applied according to the following dosing graphic:


  Weight Dose of PET-SPOT C mg Fenthion/kg body weight
Dogs 3-7 kg One pipette with 0.4 ml sol.(80 mg Fenthion) 11.4 – 26.7
7-15 kg One pipette with 0.7 ml sol.(140 mg) 9.3 – 20
15-25 kg One pipette with 1 ml sol.(200 mg Fenthion) 8 – 13.3
25-45 kg One pipette with 2 ml sol.(400 mg Fenthion) 8.8 – 16
> 45 kg 2 pipettes, each with 2 ml sol.(800 mg Fenthion) < 17.7


The second dose it will be applied, if necessary, only after 3-4 weeks.



Do not use the treatment with PET-SPOT C: in dogs under 6 months of age, weighing less than 3 kg; during the last week of gestation; in sick, stressed or convalescent animals; in other animals beside dogs.

In case of fleas’ reinvasion, another dose is applied, only after 4 weeks. It is recommended to apply the treatment in the evening, so that until morning the drug is completely absorbed in the application area. In the following 3 days after the application avoid touching and cutting the fur in the application area.

Irritation, hair loss and itches might appear in the application area. In these cases the animal should be washed with soft soap and then rinsed with a lot of water. In some cases anorexia, vomiting, diarrhea and intermittent coughing might appear. Consult the veterinarian in case the symptoms still exist.

Do not use PET-SPOT C during the last week of gestation. In 10 days before and after the treatment avoid using other cholinesterase inhibitors, phenothiazine derivatives (e.g. neuroleptics) and muscle relaxants (e.g. succinylcholine).

In case of accidental overdosing, beside the side effects, it might appear the following phenomena: miosis, hypersalivation, vomiting, diarrhea or spasms.

In this case it should be used as antidote Atropine, administrated intravenous or intramuscular, in doses starting with 0.3 mg/kg, depending on the symptoms. The repeated dozing is ceased when salivation stops. After atropinization, if necessary, it will be used cholinesterase reactivators (e.g. Toxogonin or Pralidoxime). Fenthion is incompatible with strong reducing agents, with which it might react.



Not applicable.



At temperatures below 25°C, in original packing, away from direct sunlight and freezing.



Packs with 3 doses (3 opaque plastic pipette tubes) with:

- 0.40 ml PET-SPOT C solution;

- 0.70 ml PET-SPOT C solution;

- 1.00 ml PET-SPOT C solution;

- 2.00 ml PET-SPOT C solution.



PRODUCTS FROM THE CATEGORY: Antiparasitic for dogs