Combination products can be cheaper than buying them separately. On the other hand, it can be difficult to compare the cost of combined products with separates, because it depends on the ingredients (for example, newer and potentially more effective flea treatments are more expensive than older ones) and the cost of supplying what's missing – there's no all-in-one that covers everything. And that's before you take the cost variations from retailer to retailer into account.
Fleas are a common external parasite associated with dogs. They cause severe itching and inflammation of the skin, leading to dermatitis. They are the intermediate host for the Tapeworm most common in dogs. If fleas are a problem, it is necessary to treat all animals in the household (both cats and dogs) to clean the environment. You may also want to ‘flea bomb’ the house to remove any eggs and to stop the cycle. Preventative programs are best achieved using “spot on” products that have a prolonged residual effect, usually 30 days. However it is strongly advised to consult your Vet or chat with the RSPCA's friendly Vet nurse team for free advice about the most suitable product for your pet.