Demodex are tiny mites that live in hair follicles and oil glands of the skin. Two species commonly live on humans: Demodex folliculorum and Demodex brevis. Demodex do not have anuses and cannot survive long away from a host. They feed on skin cells and oils. An overgrowth of demodex mites is called demodicosis or demodex infestation. This can cause symptoms like itching, redness, and rash. Demodex infestation may be triggered by a suppressed immune system or increased oil production. Most people have a small number of demodex mites without any problems. But others with a demodex overgrowth need treatment to reduce the mite population.
Are there oral medications for demodex mites?
Yes, there are a few oral medications that can be used to treat demodex mites. The most common oral medications prescribed for demodex include:
Ivermectin
Ivermectin is an oral antiparasitic medication often used to treat demodicosis. It helps kill the mites and reduce their numbers. Ivermectin binds to glutamate-gated chloride channels in nerve and muscle cells of invertebrates like demodex. This causes paralysis and death of the mites. Ivermectin does not significantly bind to mammalian nerve or muscle cells at normal doses. It’s thought to have anti-inflammatory effects as well, which may help reduce skin inflammation from the mites.
Ivermectin is typically prescribed in one or two oral doses initially, then repeat dosing once per week or month until the infestation is controlled. Common dosing is 200 mcg/kg. Ivermectin requires a prescription from a doctor. Side effects are usually mild but may include headaches, dizziness, nausea, rash, and swelling. Ivermectin is contraindicated in children under 5 years or under 15 kg due to risks associated with the drug crossing the immature blood-brain barrier.
Oral antibiotics
Oral antibiotics may also be used to treat demodex infestations, either alone or in combination with other medications like ivermectin. Commonly used oral antibiotics for demodex include:
– Doxycycline – A tetracycline antibiotic that has anti-inflammatory effects. Dosing is typically 100-200 mg per day.
– Minocycline – A tetracycline antibiotic similar to doxycycline that may also be used.
– Metronidazole – An antibiotic with activity against anaerobic bacteria. Dosing is 250-500 mg twice a day.
– Sulfamethoxazole-trimethoprim (Septra, Bactrim) – An antibiotic combination with activity against a broad range of bacteria.
These antibiotics are thought to help treat demodex mites both by reducing bacteria associated with the mites as well as through their anti-inflammatory effects. Oral antibiotics are often prescribed for 4-12 weeks. Potential side effects include upset stomach, diarrhea, yeast infections, and sun sensitivity.
Other oral medications
Some other oral medications that may be used for demodex mites include:
– Mebendazole – An antiparasitic sometimes prescribed for demodex, often in combination with ivermectin or an antibiotic.
– Isotretinoin – An oral retinoid drug used for severe acne that may also help reduce oil gland output and demodex populations.
– Prednisone – An oral corticosteroid with anti-inflammatory effects that may help calm skin inflammation from demodex. Short term use only.
– Hydroxychloroquine – An antimalarial drug that also has anti-inflammatory effects and may be used off-label to treat demodicosis.
Overall the main oral medications used for demodex mites are ivermectin and antibiotics like doxycycline. Other drugs may be used on a case by case basis. Any oral medication for demodex should be prescribed by a doctor after evaluation. Self-medication with ivermectin for demodex can be dangerous and is not advised.
What factors determine the choice of oral medication for demodex?
The choice of which oral medication to use for treating demodex mites depends on several factors:
Age of patient
Ivermectin should not be used in children under 5 years or under 15 kg. Antibiotics or topical treatments are preferred in young children.
Severity of infestation
For mild infestations, topical treatments alone may be sufficient. But moderate or severe infestations often need oral medication.
Extent of inflammation
If inflammation from the mites is significant, oral antibiotics or short term oral steroids may help calm this reaction.
Underlying medical conditions
Oral antibiotics like doxycycline may be preferred in patients with compromised immune systems. The doctor will consider potential medication interactions.
Patient tolerance
If the patient cannot tolerate ivermectin side effects, antibiotics or topical treatments may be preferred.
Treatment cost or availability
Ivermectin is relatively inexpensive but may not always be readily available. Generic doxycycline is often more accessible and affordable.
Prior treatment response
If the mites failed to respond to a prior medication, switching to a different oral treatment is warranted.
Overall, ivermectin and doxycycline are first-line oral treatments for demodex. But the doctor will select the most appropriate oral medication for each patient.
Are there any topical treatments for demodex mites?
Yes, there are several topical medications and creams that can be applied directly to the skin to kill demodex mites:
Permethrin
Permethrin is a topical cream that kills demodex mites on contact. It is applied to affected areas overnight then washed off. Often prescribed 2-3 times per week for 4-6 weeks.
Ivermectin cream
A topical ivermectin cream (Soolantra) is FDA approved for treating rosacea caused by demodex mites. Applied once daily at night.
Metronidazole cream
Metronidazole antibiotic gel/cream can help reduce demodex populations. Applied 1-2 times daily.
Tea tree oil
Tea tree oil has insecticidal properties and has been shown to kill demodex mites in studies. Ointments containing around 5% tea tree oil may be applied daily.
Benzoyl peroxide or sulfur ointments
These ingredients have keratolytic effects to help remove dead skin and oils where mites live. May help reduce numbers.
Essential oils
Some oils like clove, lavender, and nutmeg oils have shown demodex-killing effects in studies when applied to the skin.
These topical treatments can be effective for milder cases of demodex infestation. More severe cases may require oral medication in combination with topical creams for the best results.
What are the possible complications of a demodex mite infestation?
Most people tolerate low levels of demodex mites without issue. But an overgrowth can cause complications including:
- Severe inflammation of skin and eyes
- Blepharitis (eyelid inflammation and irritation)
- Conjunctivitis (pink eye)
- Chalazia (eyelid cysts)
- Bacterial infection of hair follicles or oil glands
- Facial redness or rosacea symptoms
- Rashes or scaly skin
- Eye damage from severe blepharitis/keratitis
- Permanent loss of eyelashes
For this reason, it’s important to treat significant demodex overgrowth either with oral or topical medications to reduce these risks. People with recurrent blepharitis or ocular rosacea should be evaluated for underlying demodex infestation. Treatment greatly improves the condition.
What is the best way to prevent getting demodex mites?
It’s nearly impossible to prevent acquiring demodex mites entirely, since they are microscopic and transmitted by close contact with people. Even newborns may have them. But some tips for prevention include:
- Wash face frequently with a mild cleanser
- Avoid sharing towels, bedding, or pillows
- Avoid touching your eyes with unclean hands
- Keep skin moisturized to avoid cracks/openings
- Don’t share eye makeup or lenses
- Clean eye makeup applicators regularly
- Remove eye makeup before bed
- Wash hands before touching eyes or applying makeup
- Practice good hygiene and don’t touch eyes with dirty hands
- See a doctor for recurring eye/skin infections
- Treat blepharitis promptly to prevent proliferation of mites
While you can pick up demodex mites from others, practicing good hygiene and avoiding eye irritation can help reduce risk and prevent over-proliferation.
Conclusion
In summary, there are oral medications that can treat an overgrowth of demodex mites, including ivermectin, antibiotics like doxycycline, and occasionally other antiparasitic or anti-inflammatory drugs. Topical creams containing ingredients like permethrin, ivermectin, and tea tree oil can also kill demodex mites on the skin. The choice of treatment depends on the patient’s age, severity of infestation, tolerance of side effects, and other factors. When indicated, treatment with oral and/or topical medications can greatly resolve inflammation, eye irritation, and skin symptoms caused by too many demodex mites. Practicing good hygiene may help prevent proliferation of mites. But even healthy people normally have some demodex mites on their skin. Overall, demodex infestations are manageable with a combination of oral and topical therapies.