To clean a lice comb, soak it in hot water of at least 130°F for 5 to 10 minutes. This kills both live lice and their eggs. But getting a comb truly clean involves more than just a hot soak. You also need to remove the debris stuck between the tines, which can be surprisingly stubborn on fine-toothed metal combs.
Cleaning Between Passes
If you’re in the middle of combing through hair, you need to clean the comb after every pass. Rinse it in a bowl of warm, soapy water and wipe it dry with a paper towel or tissue before running it through the next section of hair. This keeps you from dragging lice and nits back into clean sections of hair. Toss the paper towel in the trash and replace the soapy water if it gets visibly dirty.
Removing Stuck Debris
Nits and hair strands get wedged tightly between the narrow metal tines of a lice comb. Rinsing alone won’t always dislodge them. An old toothbrush works well for scrubbing debris out of the teeth. Dental floss is another good option, especially for combs with very tight spacing where a toothbrush can’t reach. Run the floss between each pair of tines to clear out anything stuck there. Do this over a sink or trash can so nothing falls back onto surfaces you’d need to clean later.
Sanitizing After a Combing Session
Once you’ve finished combing, the comb needs to be properly sanitized. The CDC recommends soaking combs and brushes in hot water (at least 130°F) for 5 to 10 minutes. That temperature is well above what kills lice, which die within minutes at anything over 122°F. You don’t need boiling water, but it should be hotter than what comes out of most kitchen taps, which typically max out around 120°F. Use a thermometer if you’re unsure, or heat water on the stove and let it cool just slightly before submerging the comb.
For metal combs specifically, boiling for 15 minutes is another option and provides extra assurance. Don’t boil plastic combs, though, as the heat can warp or damage them. Stick to the 130°F soak for plastic.
Using a Freezer Instead
If hot water isn’t convenient, freezing works too. Place the comb in a sealable plastic bag and leave it in the freezer overnight. Temperatures below about 0°F are lethal to lice within minutes, and a standard kitchen freezer held overnight provides more than enough exposure. After removing the comb, let it come to room temperature, then clean off any remaining debris with a toothbrush and soapy water. Throw away the plastic bag rather than reusing it.
Drying and Storing
After sanitizing, dry the comb completely before putting it away. Metal combs can rust if stored wet, and any damp comb sitting in a drawer can develop mold or a musty smell over time. Pat it dry with a clean towel and let it air dry fully before storing.
Keep the comb in a clean, sealed bag between uses, especially if you’re doing daily combing sessions over the course of a treatment. This prevents any stray hairs or debris from contaminating it and makes it easy to find for the next round.
How Quickly Lice Die Off Combs
If you’re wondering whether you really need to sanitize right away, the timeline works in your favor. Adult lice die within two days of falling off a person’s head because they can no longer feed. Nits that aren’t kept at scalp temperature typically die within a week and can’t hatch. So even if you missed a spot during cleaning, any lice or eggs left on a comb won’t survive long at room temperature. That said, the hot water soak takes under 10 minutes and gives you certainty, which is worth the effort when you’re dealing with an active infestation.