Head lice (Pediculus humanus capitis) are wingless insects that live in your hair, on the skin covering the scalp. They're small - about the size of a pen tip - with barbed legs to keep them securely on in your mane. They lay nine to ten eggs daily, attaching them to a hair shaft. Although their lifespan is only about 28 days, they can multiply swiftly. These parasitic insects are highly contagious and very difficult to kill, so early detection can help curtail the impact of the infection.
Persistent itching on the scalp is one of the first noticeable signs of head lice presence. The itching is caused by an allergy to lice bites. The lice feed on your blood from your scalp, and the saliva produced from this triggers an allergic reaction in many. For those with sensitive skin, the itching becomes noticeable sooner, but lice can be present for two to three weeks before the excessive itching begins.
Receive updates on the latest news and alerts straight to your inbox.
This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other health-care professional.