Pubic lice are parasitic insects that live on human hair and are about 1 to 3 mm long and wingless. It is called pubic lice because it is commonly found on the pubic area. The pathogenic insect of pubic lice is the pubic louse of shame. In addition, because the body of pubic lice is flattened and looks like dander from a distance, it looks like a small crab when viewed closely, so it is also called crab lice in English. Symptoms 1. Itching: Paroxysmal itching is the main symptom, but the degree of itching varies from person to person. Itching occurs when the pubic louse pierces or punctures the skin with its claw hook, and when the louse bites and injects saliva. Pubic lice inject saliva when sucking blood because saliva prevents blood clotting and facilitates blood sucking. Pubic lice suck blood several times a day, so the itching is paroxysmal. 2, rash: in the pubic lice bite often microporous (invisible to the naked eye), local redness, with small red spots, which have a blood crust; microporous about 5 days, local allergic reactions, often raised appear papules. Due to scratching often appears infection, see pustules, ooze, crust. 3.Green-gray spots: green-gray spots of 0.2-2cm in size can be seen near the affected area, which are not painful and itchy, and do not fade when pressed, and can last for several months; such green-gray spots can also be seen on the chest and abdomen, the inner side of the femur, etc. The reason for the occurrence of this greenish-gray spot is still unclear, and may be related to the saliva from the bite of the pubic lice that enters the bloodstream. Treatment of pubic lice disease: First of all, the pubic hair should be shaved and burned by fire if possible, and underwear and pants should be boiled or ironed. Topical drugs are: 1, 25% – 50% of the tincture of the hundred, applied externally 3-5 times a day for 20 days, and then applied with warm rice vinegar to destroy the adhesion between the pubic lice eggs and pubic hair, so that the pubic lice eggs can be easily removed. The concentration is not easy to control, and it is rarely used in general hospitals. 2, 10% of sulfur ointment or Ulex skin cream can be used early, for the surface of the adult lice can be killed, but for the root of the hair follicle eggs are not effective. It can be repeated after stopping the medicine and can prevent the transmission of pubic lice. 3, 10% sulfur glycolite lotion or 5% white mercury ointment can be applied to the skin lesions. You can quickly stop itching and relieve the symptoms, you can also use gynecological lotion to wash the affected area. But do not kill insects, use before buying treatment drugs.