It is common for itching to persist for some time after treatment for lice, even after the lice have been eradicated. This could be due to the treatment itself, the presence of lice residues, or heightened sensitivity. Changing temperatures can also contribute to the itching. To alleviate the discomfort, try using a gentle, fragrance-free shampoo designed for sensitive or dry scalp. You may also want to reduce the frequency of washing your hair, as frequent shampooing can strip the scalp of essential nutrients. Antihistamines like Reactine can help with itching, but it's advisable to consult a healthcare professional if you have a chronic condition or are taking other medications.