Demodecosis ointment

Ointment for demodicosis is a medicine that allows you to quickly and effectively cure a skin disease. Let's look at the main indications for using the ointment, the most effective drugs for demodicosis and the features of their use.

Ointment for demodicosis is used to combat the microscopic mite demodex, which parasitizes on human skin, affects the hair follicles of the eyelid and head. Many people suffer from demodicosis, for many, skin lesions become a real tragedy. Constant itching and peeling, the appearance of pustules, acne and rashes are the causes of not only a bad mood, but also a nervous breakdown and severe stress. Treatment of demodicosis with ointments and other drugs is quite labor-intensive and lengthy. The clutch laid by the female demodex mite goes through a development cycle of 25 days, so the minimum course of application of the ointment for demodicosis is from 30 days to one year. The duration and effectiveness of treatment depend on the neglect of the disease and the overall clinical picture.

The appearance of demodicosis can be caused by diseases of the endocrine and immune systems. Therefore, drugs used to combat skin mites should be complex, both for internal and external use. The effectiveness of the ointment for demodicosis depends on the clinical form of the disease, that is, on the prevalence of certain symptoms. A drug that helps with one form of demodicosis will be ineffective with another form. Let's look at the main forms of demodicosis:

• Erythematous (rosacea-like) – skin lesions similar to vascular neurosis, caused by fungal and bacterial microflora. The demodex mite aggravates the course of the disease, causing severe redness of the skin and acne.
• Pustular - the patient develops acne with a predominantly pustular form.
• Papular - papules appear on the face and body, from 0.5 to 4 mm in diameter, pink or bright red in color.
• Combined – all types of rashes characteristic of all forms of this disease appear on the skin.

Very often, incorrect drug treatment of demodicosis does not give the expected results or leads to relapses of the disease. If the disease is in an advanced form and has large lesions of the skin, then, most likely, there are concomitant complicating skin lesions. In this case, for the treatment of demodicosis, not only ointments are prescribed, but also antibacterial and antihistamine drugs to suppress allergic reactions from topical agents.

The main difficulty in treating demodicosis is directly related to the structural features of the mite's integument. Because of this, many ointments for demodicosis do not give a therapeutic result. The basis of therapy is a long course of treatment with the selection of effective drugs. All remedies are selected based on the results of the diagnosis of the disease and the symptoms that appear.

[ 1 ], [ 2 ], [ 3 ], [ 4 ]

Indications for use of ointment for demodicosis

Indications for the use of ointment for demodicosis are lesions of the skin of the face and body by the acne gland mite. The main symptoms of the disease that require treatment are fatigue, swelling and itching of the eyelids and eyes, hyperemia of the edges of the eyelids, plaque on the edge of the eyelids and the appearance of scales at the roots of the eyelashes. In the anamnesis, demodicosis provokes frequent styes, recurrent acne, eyelash loss and psoriasis. Let's consider the indications for the use of ointment for demodicosis using the example of two of the most effective drugs:

• Sulfur ointment

The use of the ointment is due to the fact that the drug has high antiparasitic properties. The ointment is applied to problem areas or to the entire surface of the skin, usually at night. In this case, the ointment must be applied in a thick layer, regularly changing bed linen and clothes, since the skin will peel off heavily, and parasites will die with it. The main indications for the use of the ointment: all forms of demodicosis, acne, lichen, psoriasis, fungus, seborrhea, acne.

• Benzyl benzoate

The ointment is used to treat all forms of demodicosis, rosacea, pediculosis, seborrhea. The drug is effective in the treatment of demodicosis, which is complicated by a secondary bacterial infection.

Release form

The form of release of drugs for demodicosis is varied. Ointments, creams, tablets, chatterboxes, solutions, gels, powders can be used to treat skin lesions. Let's consider the main forms of release of drugs for demodicosis, their advantages and disadvantages.

• Ointment

Ointment for demodicosis is a local application. The effectiveness of external therapy depends on the nature of demodicosis, its form, localization and depth of skin lesions. Do not forget about the pharmacological features of the ointment, as the principle of its action, and therefore the result of treatment, depends on this. Before applying the ointment to the skin, the affected area must be cleaned. The ointment may contain one or several active substances mixed with an ointment base, which is chemically neutral, does not cause irritation and does not change under the influence of body temperature.

• Powders

Such preparations for demodicosis consist of powdery substances that must be applied to the affected area of the skin in a thin layer. The peculiarity of the powder is that it degreases and dries the skin, cools it and promotes vasoconstriction. Due to this, hyperemia of the skin, swelling, itching and sensations of heat are reduced. But powders are not used for weeping wounds. Since due to mixing with exudate, they form crusts that increase inflammation and irritation of the skin.

• Gadgets

Lotions for demodicosis are used as an anti-inflammatory, disinfectant and astringent. The preparations are used only in a cooled form. A gauze bandage or napkin is moistened with the solution and applied to the affected area of the skin. Such compresses are changed as they dry, approximately every 10-15 minutes, for 1-2 hours.

• Chatterboxes

Shaking mixtures for demodicosis can be oil or water. In their structure, these are powders diluted with water and glycerin, so after application to the skin they do not crumble. After the water evaporates, a thin, uniform layer of the active substance of the drug remains on the skin, which has an anti-inflammatory effect and dries the skin.

• Cream

Cream for demodicosis is prescribed to patients with dry skin due to decreased elasticity and inflammatory processes. The cream is well absorbed into the skin, penetrating into its deep layers, has an anti-inflammatory effect and destroys the cause of demodicosis.

• Pills

Demodecosis tablets are another form of release of medicines that are used to treat skin diseases. But tablets are ineffective, since the demodex parasite very quickly adapts to the chemicals included in the drug. That is, the use of tablets does not give a visible result, but at the same time harms the body, affecting vital organs and systems. Some tablets cause allergic reactions and other uncontrolled effects.

Pharmacodynamics of ointment for demodicosis

Pharmacodynamics of ointment for demodicosis are the processes that occur with the drug after application to the skin. Let's consider the pharmacodynamics of ointment for demodicosis using two popular drugs as an example.

• Ichthyol ointment

After application to the skin, the ointment has a pronounced analgesic, antiseptic and anti-inflammatory effect. The drug is not absorbed into the systemic bloodstream, but quickly affects the parasitic tick, causing its death.

• Zinc ointment

A product with an anti-inflammatory effect. After application to the skin, the ointment has an astringent and antiseptic effect, dries wounds and has absorbent properties. The drug accelerates the process of regeneration of damaged skin tissue, forms a protective barrier and protects against irritants.

Pharmacokinetics of ointment for demodicosis

Pharmacodynamics of ointment for demodicosis is the process of absorption, distribution and excretion of the drug. After application to the skin, the ointment significantly reduces painful symptoms, itching, peeling, dryness and burning of the skin. Effective ointments for demodicosis penetrate into the deep layers of the skin and through the mite shell. This leads to paralysis and death of the parasite.

The ointment for demodicosis has an antimicrobial effect, is well absorbed and distributed. The drug has an analgesic effect. To achieve a positive medicinal effect, it is recommended to apply the ointment to the skin in a thin layer. The frequency of application is from 2 to 4 times a day. The peculiarity of the ointment is that it does not penetrate into the systemic bloodstream, but is excreted by the sweat glands in the form of sweat.

Names of ointments for demodicosis

The name of the ointments for demodicosis should be known to everyone who has encountered this kind of skin disease. Before we begin to describe the ointments, let's consider what demodicosis is. Demodicosis is a skin disease that appears due to infection with the demodex mite. With demodicosis, the skin of the nasolabial folds, chin and eyelids suffers the most. The patient develops papules, bran-like peeling and pustules. All medications for demodicosis (acaricides) have a common mechanism of action - the destruction of demodex mites. The effect on mites can be systemic, taking medications orally or applying to the affected areas of the skin.

The most famous and popular names of ointments for demodicosis are: Benzyl benzoate, Ichthyol ointment, Sulfur ointment, Zinc paste, Metrogyl jelly, Tar ointment. All ointments are antiparasitic agents, which contain substances that cause paralysis of the tick and its death. Given the tick's development cycle, the ointment for demodicosis is used from 4 to 6 weeks.

Let's look at the names of ointments for demodicosis and their principle of action:

1. Benzyl benzoate is a popular remedy for demodicosis, available in the form of an ointment and emulsion. Despite its effectiveness, the ointment can cause adverse allergic reactions. The duration of treatment and frequency of application are determined individually for each patient by the attending physician.
2. Sulfur ointment - the drug is an acaricide and is widely used to treat various skin diseases. The ointment has a paralytic effect on the tick, immobilizes it and leads to its death. The ointment contains sulfides, which accelerate the regeneration of damaged skin, restore and heal wounds.
3. Yam ointment is a bactericidal medicine that contains components with acaricidal activity. The ointment is a veterinary drug, but is also approved for use in humans. The only drawback of the ointment is its unpleasant, sharp smell and difficulty in washing off.
4. Permethrin ointment - the ointment contains substances of synthetic origin - pyrethroids, which have a minimum molecule size. The advantage of the ointment is its deep penetration into the skin and through the tick shell. Due to this, the ointment causes the death of parasites. The drug does not have an irritating effect, is low-toxic and does not accumulate in the body. It is more effective than sulfur ointment.
5. Manting - in addition to the above-described drugs, this cream is used to treat demodicosis. The drug contains only natural components that destroy the parasite. Amino acids, vitamins and extracts from medicinal herbs increase immunity and restore skin damaged by demodicosis.

Sulfur ointment for demodicosis

Sulfur ointment for demodicosis is a popular medicine that has keratolytic and antiparasitic properties. The active ingredient of the drug is sulfur, the auxiliary substances are petroleum jelly, emulsifier T2 and petroleum jelly. Sulfur ointment belongs to the pharmacotherapeutic group of antiparasitic and antimicrobial agents.

• Indications for use - sulfur ointment is prescribed to patients with skin diseases. The ointment is effective in the treatment of demodicosis, psoriasis, seborrhea, sycosis, mycosis, lichen and even scabies.
• Method of application and dosage – before applying the ointment, the skin must be cleaned. The ointment is applied to the affected areas of the skin 2-3 times a day. The thickness of the ointment layer depends on the frequency of use of the drug and the disease to be treated.
• Side effects and contraindications. In rare cases, the ointment causes increased skin sensitivity and allergic reactions. The drug is contraindicated for use in case of individual intolerance to its components.
• When interacting with other drugs, sulfur ointment can form new compounds with a very unpredictable effect. Therefore, it is recommended to avoid the simultaneous use of several ointments on one affected area of skin. Sulfur ointment should be stored at a temperature not exceeding 25 ° C, but do not allow freezing. The shelf life of the drug is 24 months from the date of manufacture indicated on the packaging of the drug.

Permethrin ointment for demodicosis

Permethrin ointment for demodicosis has medicinal properties for all forms of this disease. The drug is an effective means of destroying various types of mites. The active substance of the ointment, pyrethroids, is a substance of synthetic origin. The peculiarity of permethrin ointment is that, unlike other local drugs, its active substances pass through the thick shell of the mite.

Permethrin ointment for demodicosis has a pharmacological effect as an insecticidal and acaricidal drug. The active substance of the ointment is a synthetic pyrethroid active against demodex, scabies mites and a number of other insect parasites. The mechanism of action of the ointment is the process of destruction of nerve cells of insects, which leads to their paralysis. The ointment does not have a toxic effect on the human body.

• Indications for use of the ointment are based on the action of its active components. Permethrin ointment is used to treat scabies, demodicosis and other skin diseases. The ointment is effective for the treatment of skin lesions complicated by secondary flora, parasites and lice.
• The ointment is used externally, applying a thin layer to the affected areas of the skin. As a rule, the drug is used once, but in case of demodicosis, several courses of application of the drug are possible. It is allowed to wash off the ointment 12 hours after application, completely changing the bed linen and clothes that the patient was wearing at the time of application of the drug.
• The main side effects of the ointment are allergic reactions, burning, itching and numbness at the site of application of the ointment. In rare cases, the ointment for demodicosis causes erythema.
• Permethrin ointment is contraindicated for use by patients with individual intolerance to the active components of the drug. The ointment is prohibited for use in patients under three years of age, during pregnancy and lactation.
• Permethrin ointment is not recommended to be applied to the skin simultaneously with other medications. Local application of the ointment does not have overdose symptoms.
• The drug is available in aluminum tubes. The ointment should be stored no longer than 24 months from the production date indicated on the drug packaging, at a temperature not exceeding 25 °C.

Benzyl benzoate ointment for demodicosis

Benzyl benzoate ointment for demodicosis is a traditional remedy that has proven itself to be highly effective. The antiparasitic effect of the ointment is aimed at destroying demodex (acne gland) and scabies mites. The drug is aggressive for the skin, disrupts skin immunity and causes side effects. As a rule, for the treatment of demodicosis, in addition to benzyl benzoate ointment, doctors prescribe other drugs.

• The main indications for the use of the ointment are skin lesions caused by parasites. The ointment is effective against scabies mites and demodex mites. The drug is used to treat pediculosis and other skin diseases. The mechanism of action of benzyl benzoate ointment is based on the fact that after the tick comes into contact with the ointment, the insect dies within 10-40 minutes. The ointment penetrates the tick's shell, accumulates in the parasite's body and destroys it. The drug prevents the proliferation of pathogenic bacteria and has bacteriostatic properties.
• When treating demodicosis, the ointment is applied in a thin layer to the skin, avoiding contact with the eyes. The duration of treatment depends on the speed of skin cleansing, elimination of the main symptoms and the doctor's prescriptions.
• Benzyl benzoate ointment is contraindicated for use in cases of individual intolerance to the components of the drug, during pregnancy and lactation, as well as in cases of open wounds and pustular skin pathologies.
• Side effects of the ointment cause skin itching, erythema, dryness, burning. To eliminate side symptoms, you must stop using the ointment and consult your doctor. After completing the course of treatment, it is recommended to see a doctor for a month to monitor the condition of the skin.

Yam ointment for demodicosis

Yam ointment for demodicosis is a fungicidal and bactericidal medicine. The ointment contains: acetylsalicylic acid, sulfur, tar, turpentine, petroleum jelly, zinc oxide and other substances. Yam ointment is effective against such diseases as scabies, demodicosis, eczema, dermatitis, trichophytosis and other skin lesions. The active ingredients of the drug have acaricidal and fungicidal activity, have an antiseptic effect and astringent properties. The ointment is low-toxic and does not have an irritating or sensitizing effect.

• The main indications for using the ointment: treatment of demodicosis, eczema, dermatitis, trichophytosis and other skin diseases. The ointment is applied in a thin layer to the affected area of the skin 1-2 times a day. The duration of therapy is determined by the doctor, but, as a rule, from 10 to 14 days. After the first course of application, the patient undergoes a microscopic examination of scrapings from the affected areas. If the mite is detected, the treatment is repeated.
• Side effects of the drug are manifested in the form of allergic reactions on the skin. The ointment is contraindicated for use in case of hypersensitivity to the components of the drug.
• During the period of using the ointment for the treatment of demodicosis, it is necessary to observe the rules of personal hygiene, regularly change bed linen and clothes in which the patient is when applying the ointment. The drug is available in glass and plastic tubes.

Ichthyol ointment for demodicosis

Ichthyol ointment for demodicosis is an antiseptic preparation for local use. The ointment has anti-inflammatory, antiseptic and analgesic effects. The active ingredients of the ointment do not penetrate into the systemic bloodstream when used locally.

• The ointment is prescribed for the treatment of eczema, burns, neuralgia, joint pain and skin diseases such as demodicosis. The ointment is used externally, a thin layer is applied to the skin, but not rubbed in. After application to the skin, the treated area must be covered with a gauze bandage. The duration of the course of treatment is determined individually for each patient. But, as a rule, with demodicosis, the ointment is applied 2-3 times a day.
• Side effects of the drug are manifested as allergic reactions on the skin, itching, urticaria, rash. The drug is contraindicated for use in patients under 12 years of age and in case of individual intolerance to the components of the ointment.
• Ichthyol ointment is not recommended to be used with other topical agents on the same skin area. Since this will lead to the formation of new compounds and the appearance of uncontrolled side effects. Cases of overdose of ichthyol ointment have not been recorded.

Zinc ointment for demodicosis

Zinc ointment for demodicosis is a product for external use, which consists of two components. The ointment contains zinc and petroleum jelly. The active substance of the drug is zinc oxide, which has a pronounced anti-inflammatory effect. Zinc ointment has hygroscopic properties, effectively dries the skin, relieves inflammation and accelerates the regeneration processes of damaged skin areas.

• Indications for use of the ointment are a wide range of diseases. The drug is used to treat demodicosis, eczema, diaper rash, dermatitis of various etiologies, burns, bedsores, superficial wounds and acne, ulcerative skin lesions and other skin diseases.
• The ointment is used externally only, applying a thin layer to the affected area of the skin. The duration of use and frequency of application of the preparation to the skin depend on the symptoms of demodicosis and the form of the disease. As a rule, the ointment is applied 4-5 times throughout the day. The course of treatment is determined by the attending physician.
• The advantage of zinc ointment is that it does not cause side effects. And the only contraindication to the use of the drug is individual intolerance to the components of the ointment. That is, zinc ointment can be used during pregnancy and lactation and for the treatment of skin diseases in patients of all ages.

Trichopolum ointment for demodicosis

Trichopolum ointment for demodicosis is a medicine with the active substance metronidazole. Metronidazole is active against anaerobic and aerobic microorganisms. The mechanism of action of the drug is to damage the DNA of harmful microorganisms, which leads to their destruction and death.

• The main indications for use of the drug: infectious skin lesions and diseases caused by microorganisms sensitive to the drug.
• Trichopolum ointment is contraindicated for the treatment of demodicosis during pregnancy and lactation, as well as for patients under 6 years of age and in case of individual intolerance to the active substances of the drug.
• In case of overdose, the drug causes skin itching, burning, swelling, redness and other allergic reactions. Discontinuation of the drug eliminates painful symptoms.
• Trichopolum ointment is prescribed by the attending physician. The dosage and duration of the course of treatment is selected by the physician and depends on the form of demodicosis and the symptoms of the skin lesion.

Apit ointment for demodicosis

Apit ointment for demodicosis is a medicine with alcohol extract of propolis, lanolin and petroleum jelly. The ointment is available in 40 g jars with a uniform consistency, yellow or gray-yellow color. The medicine has anesthetic, anti-inflammatory and antimicrobial properties. The drug accelerates the process of regeneration of damaged tissues.

• The drug is used externally in the form of applications and medicinal dressings. Wipes soaked in ointment are applied to the affected area of the skin. Dressings are changed 2-3 times a day. The duration of treatment is selected individually for each patient.
• Apit ointment is contraindicated for use in case of hypersensitivity to the components of the drug. The drug does not cause side effects. The drug must be stored in a place protected from sunlight, at a temperature of up to 25 ° C degrees. The shelf life of Apit is 24 months from the date of manufacture indicated on the packaging of the drug.

[ 7 ], [ 8 ], [ 9 ]

Method of administration and dosage

The method of application and doses of ointment for demodicosis are selected individually for each patient. The doctor is guided by the form of demodicosis, the symptoms that appear, the patient's age and the presence of contraindications. As a rule, the ointment is used for a month, which allows you to destroy demodex mites throughout their entire life cycle. The ointment is applied to the skin in a thin layer 2-4 times, observing safety rules.

Let's look at the method of application and dosage of ointment for demodicosis using sulfur ointment as an example. The ointment can be used in two ways:

• The affected skin is treated daily. The ointment is rubbed into the skin with light massaging movements. It is recommended to use the preparation before bedtime and apply it to the skin for 10 minutes. A day after the last application of the ointment, you should take a shower with tar soap, change your bed linen, underwear, and outerwear.
• On the first day of treatment, all areas of the body affected by demodicosis are treated with sulfur ointment. On the second and third days of therapy, the drug is not used and do not take a shower. On the fourth day, it is necessary to take a shower with soap, change underwear and apply the ointment to the skin again. If the ointment was accidentally washed off the skin, it must be applied again. Due to the keratolytic properties of sulfur ointment, the active substances penetrate the mite faster and cause its death, eliminating itching and peeling.

[ 10 ], [ 11 ], [ 12 ], [ 13 ], [ 14 ]

Using Demodecosis Ointment During Pregnancy

The use of ointment for demodicosis during pregnancy is possible only with the prescription and permission of a doctor. During pregnancy, every woman pays special attention to her health and the health of her future baby. But sometimes the expectation of a child is overshadowed by such a skin disease as demodicosis. The expectant mother develops acne, the skin becomes bumpy, begins to peel and itch. Demodicosis during pregnancy appears due to a decrease in the protective properties of the immune system. Hormonal changes, psychological stress and frequent mood swings are factors that are the trigger for the activation of the demodex mite.

Full treatment of demodicosis during pregnancy is the use of topical agents for application to the affected skin, taking antihistamines, antibacterial and immunostimulating drugs. Pregnancy complicates the treatment of demodicosis, since some drugs, including ointments, are contraindicated for use in pregnant women. In any case, treatment should be carried out under the supervision of a doctor, with strict adherence to all his instructions.

Ointment for demodicosis during pregnancy is contraindicated to use in the first trimester. This is due to the fact that during this period, all internal organs of the child are laid and developed. To avoid abnormalities in the development of the baby, the expectant mother should refuse ointments for the treatment of demodicosis, which contain metronidazole. The substance negatively affects the development of the child and causes a number of side effects.

The use of ointments for demodicosis from the list of contraindicated during pregnancy is possible in the case when the potential benefit to the mother is much higher than the risk to the child. But there are drugs that are safe and approved for the treatment of demodicosis during pregnancy. Women are advised to wash with tar soap. Also, such ointments are prescribed as: Zinc ointment, Sulfodecortem, Dardia, Pantoderm, Tar ointment, Benzene benzoate ointment, Demalan and ointments based on hydrocortisone. The ointment can be used only after the doctor's permission and familiarization with the instructions for the drug, observing the rules for using the drug.

Contraindications to the use of ointment for demodicosis

Contraindications to the use of ointment for demodicosis are indicated in the instructions for the drug. As a rule, the ointment is contraindicated for use in case of individual intolerance to the active substances of the drug. Many topical drugs are prohibited for use during pregnancy and lactation and for the treatment of demodicosis in patients under six years of age.

Pustular skin diseases and open wounds are also contraindications to the use of ointment for demodicosis. Specific information about contraindications of a particular drug can be found in its instructions or obtained from your doctor.

[ 5 ], [ 6 ]

Side effects of ointment for demodicosis

Side effects of the ointment for demodicosis occur in isolated cases. As a rule, failure to follow the doctor's recommendations for using the drug, exceeding the recommended course of treatment and frequent application of the ointment to the skin can cause allergic reactions. The patient develops skin itching, rash, and hives. To eliminate such symptoms, it is necessary to stop using the ointment and seek medical help.

If the ointment gets into the eyes when applied to the skin of the face, the eyes must be immediately washed and drops must be applied, which will relieve inflammation, redness and prevent swelling. When swallowing the ointment for demodicosis, side effects from the gastrointestinal tract may develop. To eliminate the side effects of the drug, the patient is given a gastric lavage and prescribed absorbents.

Overdose

Overdose of ointment for demodicosis is impossible, since the external agent does not penetrate into the systemic bloodstream. But due to prolonged use, the ointment can cause allergic reactions and rash. To eliminate any side symptoms, it is necessary to stop using the ointment and seek medical help.

Interactions of ointment for demodicosis with other drugs

The interaction of the ointment for demodicosis with other drugs for local use is not desirable. It is contraindicated to apply several ointments to one affected area of skin. This is due to the fact that each ointment has its own active substances, and the interaction of such substances can lead to the formation of new compounds, the effect of which is unpredictable.

Storage conditions for demodicosis ointment

The storage conditions for the ointment for demodicosis correspond to the storage rules for any other topical preparations. It is recommended to store the medicine in a dry place, protected from sunlight and inaccessible to children. The storage temperature of the ointment should not exceed 25°C, the ointment is contraindicated to freeze, as this leads to the loss of its medicinal properties.

[ 15 ], [ 16 ]

Best before date

The expiration date of the ointment for demodicosis is indicated on the packaging of the drug. As a rule, the duration of use of the ointment is from 24 to 60 months. The shelf life of the drug is affected by the rules of its storage. If the storage conditions of the ointment are violated, it has acquired an unpleasant odor, changed color or its consistency is damaged, then the ointment is prohibited to use. Since the use of expired ointment can lead to uncontrolled side effects.

Ointment for demodicosis is the most popular remedy for the treatment of this dermatological disease. The advantage of the ointment over other forms of drug release is that the drug is applied to the affected areas of the skin, that is, the active ingredients of the ointment begin to destroy demodex mites from the first seconds. Today, the pharmacological market offers many ointments that differ in their effectiveness and mechanism of action. Only the attending physician prescribes topical agents, indicating the dosage and duration of the course of treatment for demodicosis.