Question: how long do you have lice before your head starts itching?
Answer: When you are first infected with lice, it may take up to 4 weeks for the itching to begin. After that, itching will usually happen 1 to 2 days after. Some people may not have any symptoms. You may see red bumps on the scalp and small, yellowish-white oval nits, or eggs, stuck to the hair.