CONTRIBUTOR(S): Vetstream Ltd, Linda Horspool,
Medication: Spinosad
Medication: Spinosad
Your cat has been prescribed spinosad for the treatment of flea infestations.
Key points:
• Systemic parasiticide / insecticide.
• Administer with food or immediately after feeding.
• Do not give to cats younger than 14 weeks of age.
• Do not use in cats weighing less than 1.9 kg / 4.1 lbs as accurate dosing is not possible.
• Safety in breeding and pregnant cats has not been established.
• Safety in suckling kittens has not been established – do not use in nursing female cats.
• Use with caution in cats with pre-existing epilepsy.
• Treatment of your pet’s bedding and your home with a suitable environmental insecticide may be required.
• Dosage: once a month.
This information sheet is designed to help answer commonly asked questions and help you give the medication safely and effectively to your pet. It does not contain all available information for this medication. If you have other questions or need more information, contact your veterinarian or pharmacist. Always follow the dosing instructions provided by your veterinarian.
Name, Brand names, Class of medication and Storage
Name
- Spinosad (spi -no-sad).
Brand name
- Comfortis® (Europe & UK, US).
Class of drug
- Systemic parasiticide.
- Insecticide.
Storage
- Store at room temperature.
Why has my cat been prescribed spinosad?
Your veterinarian has prescribed spinosad for the treatment of flea (Ctenocephalides felis) infestations. Spinosad kills adult fleas and prevents re-infestation for up to 4 weeks. It can also be used as part of a treatment strategy for the control of flea-allergy dermatitis (FAD).
All dogs and cats within the household should be treated and regular monthly treatments may be needed to control the flea population in contaminated households.
How is the medication given?
Spinosad is given as an oral, flavored chewable tablet. It should be administered with food or immediately after feeding.
| US | Europe | |
| Recommended dose rate/range | From 13.5 mg/lb (30 mg/kg) | 45-70 mg/kg BW |
| Tablet strength in mg | ||
| 90 | – | y |
| 140 | y | y |
| 180 | – | y |
| 270 | y | y |
| 425 | – | y |
| 560 | y | – |
Different dose rates are due to differences in the threshold for efficacy against fleas between the US (90%) and Europe (95%). Different tablet strengths are available in the US and Europe.
Are there any side-effects or drug interactions?
Vomiting in the first 48 hours after dosing is the most commonly reported side-effect and is generally transient and mild. Diarrhea and anorexia are also observed commonly. Depression/lethargy, loss of condition and salivation are observed uncommonly. Muscle tremor, ataxia and seizures, are observed rarely.
Spinosad could therefore interact with other PgP-substrates (for example, digoxin, doxorubicin) and possibly enhance adverse reactions from such molecules or compromise efficacy.
How long will my cat need to receive this medication?
As spinosad prevents reinfestation for up to 4 weeks, the tablets are given once a month. Fleas may persist for a period of time after administration of the product due to the emergence of adult fleas from pupae already in the environment. If fleas reappear in the fourth week, the treatment interval can be shortened by up to 3 days.
How should I dispose of this medication if I don’t use it all?
Dispose of any unused spinosad safely – do not flush away down the toilet or sink. Ask your veterinary team if they take back medication for disposal. Do not save spinosad for future use or give to other pets.
What if I miss a dose or give an extra dose?
If a dose is missed, administer the product with the next offering of food and resume a monthly dosing schedule. If vomiting occurs within 1 hour of administration and the tablet is visible, the cat should be given another full dose.
My cat is unwell, should I still give the drug?
If your pet is unwell, contact your veterinarian for advice.
What should I do if this medication is accidentally given to another pet or taken by a human?
Spinosad should only be given to the cat that it has been prescribed for:
- Do not use in cats and kittens younger than 14 weeks of age.
- Do not use in cats weighing less than 1.9 kg / 4.1 lbs (US) as accurate dosing is not possible.
- Safety in breeding, pregnant or lactating cats has not been established.
- Use with caution in cats with pre-existing epilepsy.
If accidentally given to other pets, contact your veterinarian for advice.
If accidentally consumed by a human, speak to your primary care physician or poison control center.
Will my cat need to be monitored while on spinosad?
There are no specific monitoring requirements.
Further information
If you have any concerns, further information on spinosad can be found on the package insert and the following websites:
Europe & UK
- European Medicines Agency Comfortis (spinosad). Summary of Product Characteristics: ec.europa.eu/health/documents/community-register/2013/20130114125064/anx_125064_en.pdf
USA
- Elanco Comfortis®. Package insert: assets-eu-01.kc-usercontent.com/ad0f862a-9fb6-0162-80e8-2abe0fae68af/c1680843-25ec-4a2a-a152-2a1dacbcf4d2/Comfortis_Pack_Insert.pdf
- Comfortis® (spinosad). Website: www.comfortis.com
Always follow the recommended dosage and contact your veterinary team or pharmacist if you have any questions regarding your cat’s medication.