Among the external parasites of dogs and cats, mites are usually not as harmful as fleas and ticks, but they can be responsible for various skin disorders (e.g. dermatitis, dermatosis) than can be severe, particularly in weak, old or otherwise weakened animals.
All mites occur worldwide, but with variable incidence depending on each species. As a general rule mite "problems" on dogs and cats are less frequent than flea or tick problems.
All mites are very small (< 0.5 mm) and only visible under the microscope. They live in or on the skin of the animals and usually do not infest internal organs. They spend their whole live on the host, i.e. there are no development step takes place off the host, e.g. on the soil. Depending on species and weather conditions they complete their live cycle in 2 to 4 weeks and do not survive off the host longer than a few days, seldom more than 2 weeks.
All mites are highly contagious among dogs and/or cat. Depending on the species they can be contagious for humans as well. However, they are not transmitted by vectors (e.g. flies, mosquitoes, etc.). Mites do not transmit microbial diseases, neither to pets, nor to humans or livestock.
Almost all mite species cause some degree of itching. In regions where fleas have a seasonal development, i.e. a no-flea season followed by a high-flea season, itching during the non-flea season may indicate a potential mite or lice problem. If inspecting the pet's coat you don't find any signs of lice (which are larger than mites), than a mite problem could be the explanation. Click here to learn more about lice on dogs and cats.
Click here to learn more about the general biology of mites.
The most important mite species of dogs and cats are the following:
- Demodex spp, demodectic mange, red mange, in dogs (Demodex canis) and cats (Demodex cati, Demodex gatoi)
- Otodectes cynotis, the ear mite, mainly in cats, occasionally in dogs
- Notoedres cati, feline scabies, itch mite, in cats
- Cheyletiella spp, walking dandruff, mainly in cats, occasionally in dogs
- Pneumonyssoides caninum, nasal mites, in dogs
- Sarcoptes scabiei, var.canis, canine scabies, in dogs
There are about 100 different Demodex species that affect all kinds of mammals. Most of them are species-specific, i.e. they infest only one or a few closely related species. Demodex canis infests dogs and other canids and occasionally humans as well. Demodex cati and Demodex gatoi infest cats and other felids, whereby Demodex gatoi is less frequent.
Demodex mites are usually not longer than 0.3 mm. They spend their whole life inside the hair follicles and/or the sebaceous glands that are attached to the hair follicles. Preferential body part is the face (nose, lips, eyebrows, etc.) but can infest the whole body, and very occasionally also the lymph nodes below the skin. They feed on
Demodex mites live mostly unnoticed as "commensals" of their host, i.e. they benefit from the host without harming it. The infestation can develop into a disease (demodectic mange) in animals weakened by other diseases, poor condition, malnutrition, age, etc. In such cases up to 75'000 mites/cm2 of skin have been recorded.
Demodectic mange tends to affect more dogs than cats, and within the dogs rather puppies and animals with short hair. Several dog breeds are more susceptible to demodectic mange (e.g. Afghan Hound, Beagle, Boxer, Bulldog, Chihuahua, Chow Chow, Dalmatian, Doberman, German Shepherd, Great Dane, Mops, Pointer, Pug, Shar Pei, Terrier, etc.).
Transmission is by direct contact, typically from nursing bitches to their puppies.
Demodectic mange is also called demodicosis, which can be localized or generalized.
Localized demodicosis is a rather benign condition characterized by small spots of hair loss with reddened skin and scale formation. It appears mostly in the face, in the forelimbs and paws, but also elsewhere. Such spots are usually not itchy. Usually it doesn't need treatment and recedes spontaneoulsy in well-nourished and healthy puppies as their immune system strengthens.
Generalized demodicosis can become a serious skin disease often affecting the whole body surface of dogs of any age. It is usually associated with a weak immune system due to age, malnutrition, other diseases (e.g. diabetes) or parasitic infestations, immunosuppressive medication, or stress (e.g. due to surgery, pregnancy, boarding, etc.). Clinical symptoms are similar to those of localized demodicosis (i.e. hair loss, reddened skin, scale formation, pustules, etc.) but often pyodermic (i.e. with formation of pus due to infection with secondary bacteria) with increased itching (pruritus), skin thickening and affecting larger skin areas or even the whole body surface. Severe generalized demodicosis can be life threatening in left untreated.
Diagnosis is confirmed by visualizing the mites in skin scrappings examined under the microscope. However, there are numerous false negatives, i.e., no mites are found in the scrapping, but the pets is indeed infested. Therefore clinical symptoms, history and response to treatment, etc. have to be always considered.
For treatment with acaricides see below.
Otodectes cynotis, ear mites, in cats and dogs
Otodectes cynotis, the ear mite, affects mainly cats and occasionaly dogs. Kittens are more at risk than adult cats. It also affects wild animals such as foxes, coyotes, ferrets, etc. The ear mite is a frequent and major cause of external otitis in cats, i.e. an inflammation of the external ear. Cat ear mites can occasionally infest humans as well.
Otodectes mites are 0.25 to 0.5 mm long. Females are larger than males. The life cycle lasts about 3 weeks. The mites live in the external ear. Sometimes they may affect other body parts, e.g. the tail. They do neither dig into the skin, nor suck blood, but feed on skin debris, exudates, which are produced as an allergic skin reaction to the mite saliva. Infections with secondary bacteria and appearance of pus are frequent, which complicate the disease.
Excess exudates and earwax build thick dark crusts that cover the external ear channel, which becomes eczematous. A dark secretion like coffee dregs accumulates in the ears. If examined under the microscope the living mites can be seen. Severe infestations can also lead to local bleeding. A possible complication is eardrum perforation with subsequent deafness and the risk that the infestation reaches the inner ear, the meninges (the brain membranes) and even the brain itself.
Affected animals suffer from intense itching and react shaking the head, licking the affected parts, vigorously scratching the ears, rubbing against objects (trees, furniture, etc.), sometimes up to self-mutilation.
Diagnosis can be made with an otoscope, which allows visualizing the mites.
Transmission among pets is by contact, typically from nursing queens to their kittens. Ear mites are highly contagious and a very brief contact is often enough for transmission.
In addition to acaricidal treatment (see below), it is mostly advisable to thoroughly clean the ear channel with disinfectants, to extract the crusts and to administer antibiotic drops to neutralize possible microbial infections.
Notoedres cati affects only cats, but it can also infest hedgehogs. It occurs worldwide but with a variable regional incidence: it is not very frequent in the USA and Northern Europe. As for all mites transmission is by contact, but physical contact between animals is not required, mites can be easily picked from shared environments.
Adult mites are 0.15 y 0.3 mm long. They look similar to Sarcoptes mites that infest dogs and livestock and have also a similar behavior. Notoedres mites dig tunnels in the skin (up to the stratum granulosum layer) where the lay their eggs. Larvae crawl out to the skin surface and dig their own tunnels where they molt to nymphs and to adults. Adults come back to the surface where they mate and start digging new tunnels. The complete life cycle lasts about 3 weeks. All stages feed on lymph and exudates produced by the skin as response to the burrowing activity and to the allergenic saliva and feces.
Infestations often begin on the head and the ears to later spread to the neck, the back, and other parts of the body.
Affected skin parts are thickened and wrinkled, with formations af crusts and scabs, often with loss of hair (alopecia). The animals suffer intense itching and react with vigorous scratching and licking the affected parts.
Diagnosis is confirmed by visualizing the mites in skin scrappings examined under the microscope. However, there are numerous false negatives, i.e., no mites are found in the scrapping, but the pets is indeed infested. Therefore clinical symptoms, history and response to treatment, etc. have to be always considered.
Occasionally Notoedres mites can infest humans temporarily, but are unable to complete development. Nevertheless, such transient infestations can also cause unpleasant itching. And although it is self-healing, as long as the cats in a household remain infested, whoever in the household can be infested again and again.
Cheyletiella mites infest mainly cats, but can also affect dogs, foxes, rabbits and also humans.
They are medium-sized among the mites (up to 0.4 mm long). They do not dig tunnels but live on the skin surface and feed on keratin, the major structural protein of the skin. Their life cycle is completed in about 3 weeks.
Cheyletiella infestations are often benign and do not cause clinical symptoms, or only mild dermatitis (skin inflammation). Massive infestations can lead to the formation of skin scales, hair loss and strong itching, often on the pet's back. It causes so-called "walking dandruff", because the moving mites carry small skin scales, giving the impression that dandruff is moving.
Diagnosis is confirmed by visualizing under the microscope the mites obtained in a skin scrapping or on a sticky tape applied directly to the skin.
Cheyletiella mites can infest humans temporarily, but are unable to complete development. Nevertheless, such transient infestations can also cause unpleasant itching, mainly on arms, belly and buttocks. They disappear spontaneously after about 3 weeks.
Infestations with Cheyletiella are also called
Pneumonyssoides caninum is a nasal mite that infests dogs and other carnivores. It occurs worldwide, but is not very frequent.
The life cycle of nasal mites is not completely understood. Usually these mites remain inside the nasal channels but a few mites may reach the outer nose. Nasal mites often cause light or no symptoms at all, but strong infestations can lead to chronic sneezing, nasal discharge, coughing, nasal bleeding (epistaxis), and restlessness. In very infrequent severe cases serious impairment of the respiratory function can occur.
Diagnosis is often difficult because the typical symptoms can be due to various other upper respiratory disorders. Diagnosis can be confirmed examining a sample of nasal discharge under the microscope or through rhinoscopy (i.e. examination of the nasal cavity with a rhinoscope).
Nasal mites of dogs are not contagious for humans, livestock or cats.
Canine scabies is caused by a dog specific strain of Sarcoptes scabiei, the responsible mite for scabies in many mammals including humans and most livestock. In fact, dog scabies can be contagious to humans and to cats, and cause a transient infestation that recedes spontaneously, because these mites do not usually complete their life cycle on humans or cats. Canine scabies is highly contagious among dogs. The reason is the mites can survive up to 2 weeks off the host and therefore transmission does not require a physical contact with other infested pets.
Adult mites are small (0.15 a 0.55 mm long) and can be seen only under the microscope. As all mite species, sarcoptic mange mites spend their whole life on the same host. The mites do not actively jump or crawl from one host to another one, but are passively transmitted when animals come in close physical contact. However, dogs can pick mites from the immediate environment. There are no external vectors that transmit the mites, e.g. insects, worms, birds, etc., as it happens with many other parasites.
The mites dig tunnels beneath the skin. Their saliva has potent digestive enzymes that dissolve the skin tissues. They feed on the resulting liquids. They do not suck blood. Adult females deposit their eggs in tunnels, which hatch in 3 to 5 days. The whole development through several larval and nymphal stages can be completed in less than 2 to 3 weeks. Adults live for 2 to 3 weeks. Off the host the mites survive only a few days.
Harm to dogs can be substantial. Mite digging causes skin irritation, which is enhanced by allergic reactions to mite saliva and feces that develop a few weeks after infestation. The affected skin develops pimples and papules that become crusty, with massive hair loss, progressive hardening and thickening, and building of skin folds. Infestations start often on the head and the ears, where the skin is thinner, to later spread to the rest of the body. Elbows, armpits, chest and belly are often affected.
Affected dogs suffer from intense itching and react shaking the head, licking the affected parts, vigorously scratching the head the ears and other affected parts, rubbing against objects (trees, furniture, etc.), sometimes up to self-mutilation.
Diagnosis is confirmed by visualizing the mites in skin scrappings examined under the microscope. However, there are numerous false negatives, i.e., no mites are found in the scrapping, but the pet is indeed infested. Therefore clinical symptoms, history and response to treatment, etc. have to be always considered.
Non-chemical prevention and control of mites on dogs and cats
Mite infestations in dogs and cats do not always develop into a disease, i.e., the infested pets do not show clinical symptoms or only mild ones, and harm to the pets is low or irrelevant. The reason is that the immune system of the pets is able to keep the mite population under "under control". If the immune system is weakened, mite numbers explode and the pet becomes sick. For proper working of the immune system it is essential to keep the animals clean, healthy and well nourished, since mites tend to proliferate in weak and neglected animals. This is particularly important for pets that are stressed (e.g. after surgery or boarding), are receiving immunosuppressive medication, or are otherwise more at risk (e.g. old animals).
To prevent mite infestations it is not necessary to systematically treat with chemical acaricides the whole household environment of the pets (carpets, mattresses, beds, cushions, coaches, cracks and crevices on floors, etc.), since mites spend all their life (including development) on the animals and those mites or eggs that fall off the animals won't survive long.
But if a pet is already infested with mites, it is recommended to wash its bed or nest and textiles in very hot water, or dry-clean them at high temperature to accelerate death of possible mites or eggs. If this is not possible, it may be better to replace them with uncontaminated fresh ones. If there is more than one pet in the same household it is also important to thoroughly clean or replace all tools or equipment used for pet care: combs, brushes, scissors, etc, to avoid passive transmission among the pets.
Vaccines, repellents and biological control of mites?
- There are no vaccines against dog and cat mites, neither to protect the pets, nor their owners. However, some people think that certain antiparasitics that are administered periodically (e.g. some spot-ons, injectables or tablets) are vaccines and write in blogs, chatrooms or forums about flea, tick or mite vaccines. Such products are not vaccines but classical insecticides or acaricides that are administered periodically and prevent re-infestations.
- There are no mite repellents, neither to prevent mite transmission from one pet to another one, nor to frighten off those mites that have already infested an animal. Most repellents may work to some extent against mosquitoes and certain flies, but certainly not against mites. To learn more about repellents click here.
- There is no biological control method to effectively prevent or cure mite infestations in dogs or cats. Learn more about biological control of ticks and mites.
Home-made traditional remedies against dog and cat mites
To begin with the conclusion, there are no natural and/or homemade remedies that will knockdown a serious mite infestation on dogs or cats. The mite population on the pet may be reduced, but the problem will not be solved. If ever effective, such remedies are frequently unreliable, i.e., they may work in a given place, on a given pet, for a certain time, but may not work elsewhere under different conditions.
There are numerous Internet sites with a lot of homemade remedies and recommendations, but almost none of them is supported by reliable investigations. Nevertheless, it may be worth trying them: usually they are not expensive and the risk of serious side effects is usually not too high. Many such remedies are based on do-it-yourself recipes based on plant extracts or products (citronella oil, neem, rosemary, lavender, lemon balm, etc.). Try them. If they work, fine. If they don't, try another one.
BUT: when dealing with plant remedies, especially self-made ones, it is good to know that the active components in herbs are also chemicals, i.e. specific molecules that have a biological effect, in this case an acaricidal effect. They have been naturally synthesized in the plants. But this says nothing about the safety of such chemicals. It is wrong and dangerous to believe that something is safe because it is natural! The most potent poisons known are often natural, i.e. of plant or animal origin. And by the way, many such "natural chemicals" are also manufactured industrially and used in numberless so-called "natural" or "biological" products".
These countless "natural" or "biological" products contain natural pesticides, or plant extracts, or mixtures in the form of spot-ons, shampoos, soaps, lotions, sprays, etc. Many of them contain natural pyrethrins that are extracted from pyrethrum or similar flowers. Such products are usually substantially less effective against mites than synthetic acaricides. Besides being less effective, many of them have a very short residual effect, i.e., they protect no more than a few hours to a few days against re-infestation. The reason is that they are easily washed away by water (rain, washing, swimming, etc.) or break down by sunlight, or they simply evaporate very quickly.
It is good to know that in many countries most "natural products" (e.g. plant extracts) are submitted to much less stringent regulations than veterinary parasiticides. This means that they don't need to proof their efficacy against parasites, or their safety for the pets, users and the environment through such strict and thorough investigations as the products containing synthetic parasiticides. Many regulatory authorities seem to simply assume that being natural they are "safe enough", or at least not harmful, and users will find out themselves whether they are effective or not... Obviously, the cost and the know-how to develop and market such "natural products" is substantially lower than for veterinary medicines containing synthetic parasiticides. This low cost explains their proliferation. It is not possible to deal with such products here in detail.
Nowadays, there are basically three types of veterinary products containing synthetic parasiticides that control mites on pets and dogs:
- Spot-ons = pipettes = drop-ons = squeeze-ons: mostly for monthly administration
- tablets, pills, etc. for oral administration: very few brands, mostly for monthly administration
- The rest: shampoos, soaps, sprays, baths, aerosols, lotions, ointments, dusts, etc: dozens of brands, the low-cost alternative
So far there are no drenches that reliably control mites on dogs and cats.
Since mites are highly contagious and infested animals not always show clinical symptoms, it is imperative to treat all dogs and cats in the same household, even if only one pet "is sick". The other ones are likely to be infested as well and will also transmit the mites to the other pets if left untreated.
When using low-cost topical products (e.g. shampoes, soaps, sprays, lotions, dusts, ointments, etc.) it is important to treat the whole body surface of the pet and not only those parts that seem most affected by the disease. The reason is that mites are not only on those parts of the pet skin that are visibly sick, but can be almost everywhere else in the pet's body.
Many veterinary products have a broad spectrum of activity, i.e. they control not only mites but also other pet parasites, e.g. fleas, ticks, gastrointestinal roundworms, heartworms, tapeworms, etc. Since your pet may need treatment or protection against some of these other parasites as well, it can make sense to select a product based on its spectrum of activity.
But be aware that not all veterinary products for flea and/or tick control on pets are effective against mites as well. And within those that control fleas/and or ticks, almost no product controls all mite species. Most such products control one or two mite species, but not all species. Other products may control a particular species but only at a dose that is higher than the recommended therapeutic dose. Summarizing, it is your veterinary doctor who can determine the particular mite species that affects the pet, and which treatment is the most appropriate.
Spot-ons are ready-to-use concentrates containing one or more active ingredients with parasiticidal efficacy. Depending on the active ingredient(s) they are effective against other pet parasites, e.g. ticks, fleas, gastrointestinal worms, heartworms, etc.
Spot-ons are medicines for topical administration, i.e. they are applied on the skin of the pets. They are often sold in single-use squeezable vials or ampoules of different sizes for dogs or cats in a particular weight range. The whole content of a vial is applied on a given "spot" (typically on the neck or on the back). Once applied to the skin, the active ingredient spreads throughout the body of the pet or is absorbed through the skin into the pet's organism (so-called systemic products). Both spreading and/or absorption through the skin can be slower or faster, more or less complete, etc. depending on each animal's features (e.g. size, breed, hair coat, behavior, etc.) and also on the non-active, inert ingredients in the product, i.e. on its formulation, which can vary significantly between manufacturers. This is why product quality (and safety!) depends not only on the active ingredient(s), but also on the formulation (which is true for spot-ons and for whatever parasiticide or medicine, veterinary or human).
Most spot-ons are quite resistant to occasional washing and shampooing, i.e., the pet won't loose protection against mites after a splash. But repeated splashes or shampooing can indeed diminish the length or protection.
Click here to learn more about spot-ons, pipettes, squeeze-ons: efficacy, safety, etc.
The best known original spot-on brands that control mites are the following (not all available worldwide):
- ADVOCATE = ADVANTAGE MULTI from BAYER, for dogs and cats, with imidacloprid and moxidectin. ADVOCATE is approved for ear mite (Otodectes cynotis) control in cats, but is not indicated against any dog mites. Moxidectin is a broad-spectrum macrocyclic lactone that controls also major roundworms, including heartworms, as well as several lice and mite species, but is not effective against fleas or ticks. Moxidectin has a systemic mode of action, i.e. although topically administered, it is absorbed through the skin into the pet's blood and distributed throughout the whole body. Moxidectin is also used on livestock but not in agriculture or hygiene. Imidacloprid is a broad-spectrum contact insecticide that kills adult fleas (adulticide) and belongs to the neonicotinoid pesticides. Besides fleas it also controls a few lice species, but not ticks. Imidacloprid is also vastly used in agriculture as well as in public and domestic hygiene.
- CERTIFECT, from MERIAL, only for dogs, with amitraz, fipronil and methoprene. CERTIFECT'S US product label states that the product "aids in the control of sarcoptic mange infestations." The EU label does not include any mites among the parasites controlled by CERTIFECT. Amitraz is a veteran amidine acaricide and louisicide effective against ticks and mites. Fipronil is a broad-spectrum contact insecticide and acaricide that kills the fleas and belongs to the phenylpyrazole pesticides. Methoprene is a juvenile hormone analogue, i.e. an insect development inhibitor, which prevents deposited flea eggs from hatching, because a few adult fleas may survive the fipronil treatment. It has no efficacy whatsoever on mites. All three active ingredients are non-systemic. Fipronil, methoprene and amitraz are all pesticides used also on livestock and agriculture. Amitraz is toxic for cats !
- PROMERIS DUO, from FORT DOGE (→ PIZER→ZOETIS), only for dogs, with amitraz and metaflumizone. PROMERIS DUO is approved in the EU for control of Demodex mites. Amitraz is a veteran amidine acaricide and louisicide effective against ticks and mites. Metaflumizone is a broad-spectrum insecticide effective against adult fleas, but not against mites or ticks. It belongs to the semicarbazone pesticides. It was introduced by BASF for agricultural use in 2000. BASF does not market veterinary products. Both active ingredients are non-systemic. Amitraz is toxic for cats !
- NOTICE: In 2011 FORT DODGE announced the withdrawal of PROMERIS and PROMERIS DUO from the market for not fitting with their product range. The decision was perhaps related to reports that associated metaflumizone with a higher incidence of "pemphigus foliaceus" in pets, a type of autoimmune skin disorder. However, it is not clear whether this withdrawal has become effective worldwide. Some Fort Dodge websites (e.g. Brazil in January 2013) still include PROMERIS and PROMERIS DUO in their product range.
- REVOLUTION = STRONGHOLD, from PFIZER (→ZOETIS) for dogs and cats, with selamectin. REVOLUTION = STRONGHOLD is approved for the control of Otodectes and Sarcoptes mites. There are reports on acceptable control of Cheyletiella and Notoedres mites, but not of Demodex mites. Introduced in the late 1990s. Selamectin is a macrocyclic lactone effective against adult fleas, certain lice, and tick species as well as against roundworms, including heartworms. Selamectin has a systemic mode of action, i.e., it is first absorbed through the skin into blood and then distributed through the whole body of the pet.
So far there are very few products for oral delivery approved for the control of mites of dogs and cats. The most relevant one is:
- INTERCEPTOR, from ELANCO (NOVARTIS), for dogs and cats, with milbemycin oxime. INTERCEPTOR is approved in several countries for the control of Demodex canis, Sarcoptes scabiei, and Pneumonyssoides caninum in dogs. However, the US label does not include any mite species. Milbemycin oxime is a broad-spectrum macrocyclic lactone highly effective against heartworms and the most important gastrointestinal roundworms of dogs. Milbemycin oxime has no efficacy against fleas or ticks. Milbemycin oxime is exclusively used on pets, not on livestock or in agriculture.
- Other related ELANCO (NOVARTIS) brands for oral administration containing mibemycin oxime do not include any pet mite species in the approved indications: SENTINEL = PROGRAM PLUS (with milbemycin oxime and lufenuron), SENTINEL SPECTRUM (milbemycin oxime, lufenuron and praziquantel), MILBEMAX (with milbemycin oxime and praziquantel).
- SIMPARICA, with sarolaner, from ZOETIS. Availabe only for dogs in certain countries. Introduced in 2016. Sarolaner is one of the newest insecticidal active ingredients from the chemical class of the isoxazolines. For monthly administration against ticks, fleas, and certain mite species (Sarcoptes scabiei, Demodex canis, Otodectes cynotis). There are no generics.
Ivermectin products for oral delivery (e.g. HEARTGARD and HEARTGARD PLUS from MERIAL) do not include any pet mite species in the approved indications.
Click here to learn more about pills, tablets, etc.: efficacy, safety, etc.
In most countries there are no injectables approved for the control of mites on dogs and cats.
Among the numerous chemical classes of parasiticides, only the macrocyclic lactones are appropriate for use as injectables against various mite species. However, whereas several macrocyclic lactones are enormously used as injectables on livestock, there are almost no injectable macrocyclic lactones for pets. In some countries the classical 1% injectable formulation of ivermectin for livestock is also approved for use on dogs and even cats. But in most countries, including the EU and the USA this classic 1% ivermectin formulation is usually not approved for use on cats and dogs (see table below for a summary on macrocyclic formulations for pets and livestock)
|Abamectin||Injectables, Drenches, Pour-ons||Tablets, Injectables|
|Ivermectin||Injectables, Drenches, Pour-ons||Tablets|
|Moxidectin||Injectables, Drenches, Pour-ons||Tablets, Injectables|
Interestingly, there is a high demand for using injectable macrocyclic lactones (especially ivermectin) on dogs and cats. This site receives dozens of daily visits from people searching information on this topic, especially dosing. It is obvious that many veterinarians want to use such injectables on dogs and cats but do not find appropriate information in official sites from manufacturers or registration authorities, simply because they are not approved for it.
In most countries veterinary doctors can prescribe off-label use of whatever veterinary medicine. However, extreme care must be taken when using injectable macrocyclic lactones off-label on dogs and cats, especially those approved for livestock but not for pets. The reasons are the well-known problem of MDR-1 dogs' intolerance to macrocyclic lactones, the risk of adverse reactions if the treated pet is infested with heartworms (Dirofilaria immitis), and also that livestock formulations may not be tolerated by pets. It is also crucial to consider that the tolerated dose is lower after injection than after oral or topical administration, and that the dose required for controlling mites is often higher than the dose for heartworm prevention or other indications in the product's label. Finally, the pharmacodynamics of the active ingredient inside the pet's body depends also on the product's formulation, which is mostly different for each brand. Summarizing, off-label use of macrocyclic lactones on dogs and cats is possible, but risky, and should always be controlled by a veterinary doctor!
Click here to learn more about injectables: efficacy, safety, etc.
A common feature of all these products is that none has a systemic mode of action, i.e. all work only by contact. As a consequence, it can happen easily that parts of the pet's body remain insufficiently treated by the product, allowing mites to survive and to re-start the infestation. Therefore, such topical products are often less reliable than systemic products for mite control.
Many products of this category contain veteran broad-spectrum acaricides such as organophosphates (e.g. chlorfenvinphos, chlorpyrifos, coumaphos, diazinon), synthetic pyrethroids (e.g. cypermethrin, deltamethrin, permethrin) and/or amitraz. Not all are reliably effective against pet mites, because the main target parasites of such products are usually fleas, lice and ticks. Lime sulfur is often also used against pet mites.
To ensure complete coverage of the whole body surface dipping the pet is usually the most reliable approach. However, it has to be repeated several times, typically 3 to 4 times with an interval of about 2 weeks.
Click here to learn more about shampoos, soaps, baths, sprays:efficacy, safety, etc.
Most insecticide-impregnated collars for pets are not approved for mite control in most countries. Such collars target mainly fleas and/or ticks. Even one of the newest collars, SERESTO from BAYER with flumethrin and imidacloprid, does not include mite species in its label, although there are publications that it controlled Sarcoptes scabiei 3 months after application.
Clik here to learn more about insecticide-impregnated collars: efficacy, safety, etc.
So far there are almost no reports on confirmed resistance of dog or cat mites to acaricides.
This means that if a particular product has not achieved the expected control, it is most likely because the product is not adequate or it was not used correctly, not because mites have become resistant.