Fleas and Ticks

Over 68 aerosol products containing isopropyl alcohol solvent have been reported (145). Aerosol formulations include hair sprays (146), floor detergents (147), shoe poHshes (148), insecticides (149,150), bum ointments (151), window cleaners, waxes and poHshes, paints, automotive products (eg, windshield deicer), insect repellents, flea and tick spray, air refreshers, disinfectants, veterinary wound and pinkeye spray, first-aid spray, foot fungicide, and fabric-wrinMe remover (152) (see Aerosols). 

There are several unique topical dosage forms for animals. Four types of which the pharmacist should have a basic understanding or awareness are (a) pour-on/spot-on applications, (b) dust bags, (c) dips, and (d) flea and tick collars. These are used for treatment and prevention of internal and external parasites. 

This dosage form will be most familiar to the pharmacist since it is used for companion animals (dogs and cats) and is sold in most drugstores, supermarkets, and animal health product centers. There are two types of flea and tick collars, also known as slow-release pesticide generators vaporous and powder-producing collars. Both contain the insecticide and a plasticized solid thermoplastic resin. 

Fenvalerate toxicity is antagonized by atropine sulfate or methocarbamol, which may be effective in treating severe cases of poisoning (Hiromori et al. 1986). Conversely, some compounds exacerbate the toxicity of fenvalerate and interfere with a desired use. Domestic cats (Felis domes-ticus) treated with Fendeet (an aerosol mixture of fenvalerate and A-A-diethyl-m-toluamide) to control fleas and ticks sometimes show signs of toxicosis, such as tremors, hypersalivation, ataxia, vomiting, depression, and seizures. Signs usually appeared within hours of topical application, and females and juveniles seem to be the most sensitive groups. The demonstrated ability of N-N-diethyl-m-toluamide to enhance the dermal absorption of fenvalerate is the probable cause of toxicosis (Dorman et al. 1990). 

Topical aerosol treatment of fenvalerate plus Deet (N-N-diethyl-m-toluamide) to control fleas and ticks... 

Lindane was widely used because it killed a broad range of insects from fleas and ticks to worms that damaged crops. For a time it was even used to kill rodents. 

As an example, reaction of an acid chloride with diethylamine forms the 3° amide A,7V-diethyl-w-toluamide, popularly known as DEET. DEET, the active ingredient in the most widely used insect repellents, is effective against mosquitoes, fleas, and ticks. 

Fenthion is a broad spectrum insecticide. When applied as a surface spray, it controls adult mosquitoes and other insect pests and spiders in agricultural, horticultural, and home garden use. Recent reports indicate that resistance to fenthion has developed in some species of mosquitoes. Fenthion is used in dermal application for treatment of swine and cattle for control of lice, flies, and ticks, and in flea and tick treatments for pets. It is also used in aqueous applications to kill dragonfly larvae in ornamental fish production ponds. Fenthion is an effective avicide, and has been marketed to control birds considered to be pests. 

Imidacloprid is a neonicotinoid insecticide that is registered for many uses, including grub and termite control, crop protection, and to control fleas and ticks on companion animals. Its insecticidal activity is attributed to nicotinic activity on post-synaptic receptors. 

Dogs and cats are commonly poisoned by pesticides, herbicides, household products such as antifreeze, and drugs such as acetaminophen applied by humans to their pets. By far the most common toxicities in these small animals involve various insecticides and the overzealous use of these products by owners attempting to control fleas and ticks on their pets. 

The safety and immediate efficacy of pyreLhrins synergizod with PBO has been recognized for many decades, and they remain the most common combinations of insecticide/acaricide products for direct application to both humans and animals. Lice and crabs have to be controlled with safe, effective products since they involve direct application to humans. Similarly flea and tick control involves direct application to pets, many of which arc sensitive to pesticides. 

A desiccant dust containing amorphous silica gel in combination with 1.00% pynelhrins and 10.00% PBO can be applied as a crack and crevice treatment against fleas and lice and may also be applied directly to the animal. A companion formulation containing 0,50% pyrethrins and 5.00% PBO in a silica gel base is designed for use on zoo and laboratory animals including monkeys, chimpanzees and rodents. Both products kill lice, fleas, and ticks on contact by a combination of physical dehydration and chemical action. 

Lotions and mists for the control and rcpellency of ear mites of dogs/puppies. cals/kittens, and rabbits are frequently formulated with PBO. A typical formulation will contain 0.15% pyrethrins synergized at a I 10 ratio with PBO-Since synergized pyrethrins are not cholinesterase inhibitors, they may be used in conjunction with flea and tick dips, collars and oral medications- Products based on pyreth ram and PBO offer veterinarians safe, effective residual action without (he inclusion of toxic additives and without restrictions on repeat applications or concomitant treatments with other insecticides or anthelmintics (MacDonald and Miller, 1986). 

Summary A 40-year-old male who presents with migrating arthralgias and nen-rologic changes which were preceded by a centrally clearing circular rash, myalgias, and headache after a hunting trip where he was exposed to fleas and ticks. 

More than 9000 chemicals were tested as repellents for mosquitoes and other biting flies, chiggers, fleas, and ticks before 1960, primarily for military use (Smith et al., 1960). N,N-diethyl-m-toluamide (DEET) proved to be the most outstanding all-purpose individual repellent and is still the most useful substance today. 

Carbaryl is a reversible, carbamate-derived AChEI that has tremendous economic impact as an insecticide for use on houseplants and vegetables as well as for control of fleas and ticks on pets. Its structural relationship to physostigmine and neostigmine is readily apparent. A number of other carbamate AChEls also are commercially available for this use. 

Products and Uses In flea and tick collars, sprays, and roach and ant killers. An insecticide for animal feed, cereals, cookies (packaged), crackers (packaged), figs (dried), flour, pork, and sugar. Excellent for controlling spiders and flying insects. 

A CEC separation of insecticidal pyrethrin esters was accomplished by Henry et al. [63]. Here it was shown that it is possible to identify pyrethrin esters (cinerin I, pyrethrin I, jasmolin I, cinerin II, pyrethrin II, and jasmolin II) in a commercially available pyrethrin dip and flea and tick mist (Figure 5.20). The column inner and outer diameters were 100 and 350 (im, respectively, and the total and effective lengths were 33 and 25 cm, respectively. The column was packed with 3 xm particle size Hypersil C18. The mobile phase was composed of 55 35 10, pH 9, ACN-25 mM Tris-tetrahydrofuran. Other parameters were an applied voltage of 30 kV, column temperature of 25°C, and UV detection at 254 mn. 

FipronU has high intrinsic activity against a wide range of animal health pests and has become the standard treatment for flea and tick control on domesticated animals. Cat fleas Ctenocephalides fdis) are extremely sensitive to fipronil [128] when apphed as either a spray [129] or a spot-on [130] formulation to companion animals. Fipronil is also highly active on ticks [131,132] and has been shown to reduce the transmission of the tick-home causative agents of canine diseases [133, 134]. Fipronil has also been shown to control biting lice on both dogs and cats [135, 136], Fipronil is applied as both a spray and a spot-on treatment as well as a combination product with s-methoprene. 

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