3 doctors weighed in:

How long can you have lice before showing symptoms?

3 doctors weighed in
Dr. Michael Tomeo
Dermatology
1 doctor agrees

In brief: A few days

They multiply quickly and show nits in the hairs and can cause itch.

In brief: A few days

They multiply quickly and show nits in the hairs and can cause itch.
Dr. Michael Tomeo
Dr. Michael Tomeo
Thank
Dr. Willa Terry
Pediatrics

In brief: Weeks

Head lice can live up to 30 days on a human and heir eggs can live for more than 2 weeks, so that is why it is so hard to get rid of lice.
Symptoms can include intense itching of the scalp and visible lice and nets at the hair shaft. Fortunately, although a nuisance, lice do not transmit infectious diseases.

In brief: Weeks

Head lice can live up to 30 days on a human and heir eggs can live for more than 2 weeks, so that is why it is so hard to get rid of lice.
Symptoms can include intense itching of the scalp and visible lice and nets at the hair shaft. Fortunately, although a nuisance, lice do not transmit infectious diseases.
Dr. Willa Terry
Dr. Willa Terry
Thank
Read more answers from doctors