New methods of flea control in dogs

New products such as Program, Advantage, Advantix, and Frontline have practically replaced the use of oral Proban (a twice weekly tablet or liquid used to kill fleas and ticks that bite your dog) and dips, powders, sprays, and shampoos to treat and prevent fleas. The new products are more effective and safer than the traditional insecticides. They are also easier to administer.

Program (the brand name for lufenuron) was the first and remains one of the most popular agents for controlling fleas on dogs. Program is a tablet given once a month with a meal. The active ingredient accumulates in the dog’s subcutaneous tissue and requires that the flea bite the dog in order to work.

Program works by inhibiting flea eggs from growing and hatching. This leads to a steady drop in the number of new fleas in the environment. Its affect is limited to the hard outer shell of the flea, making it completely harm- less to mammals. However, because mature fleas are not affected, it can take 30 to 60 days or longer for the adult fleas on the dog to die of old age before you notice a reduction in itching and scratching.

For more immediate results, and especially if the dog is suffering from flea allergy dermatitis, Program should be combined with a flea shampoo or some other topical insecticide treatment. Advantage or Frontline can be added to program to kill adult fleas within one to two days. It may be necessary to eliminate fleas on the premises using insecticides, as well (see Eliminating Fleas on the Premises).

Program should not be used on puppies younger than 6 weeks of age, but is safe to use on pregnant and lactating bitches.

Sentinel combines Program with the heartworm preventive Interceptor. This broad-spectrum preventive not only controls fleas, but also protects against heartworms, ascarids, hookworms, and whipworms.

Advantage (imidacloprid) is a once-a-month liquid preparation that kills fleas by direct contact. Fleas don’t have to bite the dog for the preparation to work. Advantage comes in a tube and is applied to the dog’s skin between the shoulder blades (you must carefully part the hair to make sure you get the liquid on the skin) and to three or four additional sites along the dog’s back for larger dogs. The amount to apply depends on the size of the dog, and will be prescribed by your veterinarian. One application protects a dog for up to 30 days.

Advantage kills fleas on direct contact and may reduce hatching eggs and larvae. Following application, 98 to 100 percent of adult fleas are killed within 12 hours. Thus, any new fleas that infest the dog should be killed before they have a chance to lay eggs. This breaks the flea life cycle and eventually eliminates fleas in the environment. Advantage is not absorbed into the dog’s system, and therefore is nontoxic. Humans do not absorb the chemical after petting a treated dog. Advantix is a new formulation that also acts against ticks.

One drawback of Advantage is that it loses some of its effectiveness if the dog’s coat becomes thoroughly wet more often than once a week. If this hap- pens, the dog can be retreated as often as once a week.

Advantage should not be used on puppies under 7 weeks of age, or on pregnant or lactating females.

Frontline and Frontline Spray contain the active ingredient fipronil, which kills fleas on contact within 24 to 48 hours. The fleas do not need to bite the dog to be killed. Frontline is a liquid that comes in tubes and is applied as described for Advantage. The effectiveness of Frontline is not diminished if the dog’s coat becomes wet. The product has a residual effect that lasts up to 90 days in some dogs. Like Advantage, Frontline is not absorbed and thus appears to be nontoxic. One additional benefit is that it also kills ticks for up to 30 days. Frontline should not be used on puppies under 10 weeks of age.

Frontline Plus has (S) methoprene, which is labeled to kill adult fleas, flea eggs, and larvae. It also treats chewing lice and is used as part of a program to control sarcoptic mange. Frontline Plus is labeled for puppies 8 weeks of age. It is also labeled for use on breeding, pregnant, and lactating bitches.

The heartworm preventive Revolution (selamectin) is a once-a-month liquid preparation applied to the skin of the dog’s neck between the shoulder blades, as described for Advantage. It also controls adult fleas and prevents flea eggs from hatching. It is discussed in the section on Heartworms.