It’s also important to note quarantine procedures are important to follow because if they’d been in the same room or I wore the same clothes around them I could easily spread the lice.
I always have Revolution on hand. I buy it from Petshed.com without a prescription but it takes awhile to get here since it's coming from Australia (or New Zealand? I can't remember). However, you can also use ivermectin to get rid of lice.