Spinosad
Also known as: Comfortis, Natroba, Extinosad, Trifexis
### Administration Guidelines * **Give with a full meal:** Food is required for the medication to be properly absorbed into your dog's system. * **Vomiting:** If your dog vomits within one hour of taking the tablet, you should give another full dose to ensure they are protected. * **Missed Doses:** If you forget a dose, give it with food as soon as you remember, and then resume your normal once-a-month schedule from that new date. > **Important Note:** These chewable tablets are beef-flavored but actually contain pork proteins and hydrolyzed soy. If your dog has a known food allergy to pork or soy, please inform your veterinarian.
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- Flea infestation
- Prevention or treatment of fleas infestations
- Flea infestation
How it is given
Possible side effects
- Vomiting (most common)
- Depression/lethargy
- Anorexia
- Ataxia
- Diarrhea
- Pruritus
- Trembling
- Hypersalivation
- Seizures (rare)
- Vomiting (occasional)
- Lethargy (rare)
- Diarrhoea (rare)
- Anorexia (rare)
- Ataxia (rare)
Cautions & contraindications
- Cats (per this specific monograph's label status)
- Dogs with known pork or soy allergies (chewable tablets contain pork proteins and hydrolyzed soy)
- Dogs and cats weighing < 1.2 kg
- Dogs and cats < 14 weeks of age
- Dogs with MDR1 mutation (relative contraindication due to increased risk of adverse effects)
- Use with caution in **breeding females** and dogs with **pre-existing epilepsy**, as higher than labeled dosages may decrease the seizure threshold. Safe use in breeding males has not been evaluated. The chewable tablets contain pork proteins and hydrolyzed soy; use cautiously in dogs with severe food allergies to these ingredients.
Drug interactions
- Ivermectin: Concurrent use with high extra-label doses of ivermectin (e.g., for demodicosis) increases the risk of neurotoxicity. However, spinosad is safe to use with standard low-dose heartworm preventatives.
- Macrocyclic lactones (e.g., avermectins, ivermectin): Increased risk of severe neurological toxicity. Do not use in combination.
- Digoxin: Competition for P-glycoprotein efflux pump, potentially increasing digoxin levels.
- Doxorubicin: Competition for P-glycoprotein efflux pump, potentially increasing doxorubicin toxicity.
Frequently asked questions
What is Spinosad used for in pets?
### Administration Guidelines * **Give with a full meal:** Food is required for the medication to be properly absorbed into your dog's system. * **Vomiting:** If your dog vomits within one hour of taking the tablet, you should give another full dose to ensure they are protected. * **Missed Doses:** If you forget a dose, give it with food as soon as you remember, and then resume your normal once-a-month schedule from that new date. > **Important Note:** These chewable tablets are beef-flavored but actually contain pork proteins and hydrolyzed soy. If your dog has a known food allergy to pork or soy, please inform your veterinarian.
Is Spinosad safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
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