Treat My CatGuides › Skin and parasites
How to treat fleas on your cat (and get them out of your home)
Fleas are the most common parasite in cats, including indoor cats. They hitch a ride in on people, other pets and visitors. The good news is that they're very treatable. The catch is that the fleas you see on your cat are only about 5% of the problem. The rest are eggs, larvae and pupae in your carpets, bedding and sofa.
Signs your cat has fleas
- Scratching, especially around the neck and the base of the tail
- Over-grooming, or bald patches on the belly and back legs
- Small scabs along the back (often called miliary dermatitis)
- "Flea dirt": tiny black specks in the fur. Put a few on damp white kitchen paper. If they smudge reddish-brown, that's digested blood and you've found fleas.
- Tapeworm segments that look like grains of rice near the bottom. Cats catch tapeworm by swallowing fleas while grooming.
Step 1: treat every pet in the house
Use a licensed flea treatment made for cats, at the right dose for your cat's weight. The most effective options are:
| Type | How it works | Good to know |
|---|---|---|
| Spot-on (applied to the back of the neck) | Spreads through the skin oils and kills fleas for about a month | The most popular option. Part the fur so it reaches skin. |
| Oral tablet | Kills fleas that bite within hours | Handy if spot-ons irritate your cat. Some last 1 to 3 months. |
| Long-acting collar | Slowly releases treatment for several months | Choose one with a quick-release safety catch. |
Prescription products from your vet usually work better than older supermarket ones, because fleas in many areas have become resistant to some older ingredients. If you've used a product correctly and still see live fleas after a few weeks, ask your vet about switching.
Treat every cat and dog in the house at the same time, or the fleas simply move to the untreated animal.
Step 2: treat your home
Most of the flea population lives in your home, not on the cat.
- Vacuum daily for two weeks: carpets, rugs, sofas, under furniture and along skirting boards. The vibration also makes pupae hatch, so the treatment can kill them. Empty the vacuum outside each time.
- Wash bedding (the cat's and anywhere it sleeps) on a hot wash, 60°C / 140°F if the fabric allows.
- Use a household flea spray containing an insect growth regulator (such as methoprene or pyriproxyfen), which stops eggs and larvae developing. Keep cats and fish out of the room until it's dry, and follow the label.
Step 3: be patient and keep going
Expect to see some fleas for up to 6 to 8 weeks. That's new fleas hatching from pupae in the home and dying when they jump on your treated cat. It doesn't mean the treatment has failed. Keep treating monthly (or as the product says), and carry on through winter, because central heating keeps fleas breeding all year.
Never use these on a cat
- Dog flea products. Many contain permethrin, which is highly toxic to cats and can cause tremors, seizures and death, even from close contact with a freshly treated dog. If this happens, call your vet or an emergency clinic straight away.
- Essential oils (tea tree, eucalyptus, citrus, peppermint). Cats can't process them properly and they can cause poisoning.
- Garlic, vinegar sprays or "natural" home remedies. They don't work and some are harmful.
- Flea treatments on kittens unless the label says they're safe for that age and weight.
When to see a vet
- Kittens, elderly cats or very small cats with lots of fleas. Heavy infestations can cause anaemia (look for pale gums, weakness or tiredness).
- Sore, broken or infected skin from scratching.
- Your cat seems unwell after a flea treatment: drooling, twitching, wobbliness or hiding. Wash the product off with mild washing-up liquid and call your vet.
- You still see live fleas after 8 weeks of correct treatment.
The short version
Treat all pets with a cat-safe product, treat the home, and keep going for two months. Then stay on monthly prevention so it doesn't happen again.