Scabies, caused by the Sarcoptes scabiei mite, is a common skin problem that spreads easily. It causes intense itching and small bumps on the skin. Ivermectin, a medicine that kills parasites, has become an effective cure for scabies, especially when creams do not work or are hard to use.
Ivermectin works by disrupting the nervous system of the mites. It attaches to special channels in their nerve and muscle cells. This makes the cells more open to chloride ions, which stops the mites from moving and makes them die. Unlike creams applied to the skin, oral ivermectin treats the whole body at once. This makes it useful in cases where many mites are present or in crusted scabies.
Many studies and guidelines from health groups like the World Health Organization and the CDC support using ivermectin for scabies. They say it works well for many parasitic diseases.
Finding the right dose of ivermectin is very important. The usual dose is one single oral dose of 200 micrograms for each kilogram of your body weight. This is about one 3 mg tablet for every 15 kg, or about 33 pounds.
For a 70 kg adult, the dose would be: 70 kg x 200 mcg/kg = 14,000 mcg, or 14 mg. To take 14 mg, you need about five 3 mg tablets.
Many people ask if one dose is enough. Research shows that while a single dose helps reduce symptoms, a second dose can better eliminate all mites and stop new ones from growing.
Many studies show that two doses of ivermectin work better than one. A study in the International Journal of Dermatology found that two doses had higher success rates in clearing scabies and stopping it from coming back.
When choosing treatment, people often compare oral ivermectin to creams like permethrin. Each has good points and some risks.
Oral ivermectin covers the whole body. It is simple to give and works well, especially in tough cases or crusted scabies. It is best when topical creams are hard to use. It may cause side effects like stomach pain or dizziness. It is not safe for pregnant women or children under 15 kg.
Creams like permethrin are applied directly to the skin. They work well and have little effect on the rest of the body. But they need to be spread over the whole skin, which can be hard. Some people may get skin irritation or allergic reactions.
Doctors usually use ivermectin pills when creams do not work, when the problem is severe, or when it is hard for the person to use creams. Sometimes, using both pills and creams can give better results.
A common question is how long it takes to feel better after starting treatment. The drug works quickly to kill the mites, but symptoms like itching may last longer. This is because the body's immune system reacts to dead mites and their waste, and the itching can stay for some time.
It is also very important to treat all close contacts and household members at the same time. Since scabies spreads easily, treating only one person can lead to the problem coming back. Treating everyone at once helps stop the mites from spreading again.
Sometimes, ivermectin may not work well. This can happen if the dose was wrong, if the mites are resistant, or if new mites are picked up after treatment.
