Cleaning a lice comb takes two steps: wipe it between passes through the hair, then soak it in hot water (at least 130°F) for 5 to 10 minutes when you’re done. That combination removes visible debris during combing and kills any lice or eggs left on the teeth afterward.
Clean the Comb Between Each Pass
Every time you pull the comb through a section of hair, check the teeth. If you see lice or nits caught in the comb, dunk it in a bowl of soapy water and swish it around, then wipe the teeth dry with a paper towel or tissue before running it through the next section. This prevents you from redepositing what you just removed back onto the scalp. Keep the bowl of soapy water nearby for the entire combing session, and replace it if it gets visibly dirty.
Nits can cling stubbornly between the fine teeth of a lice comb. If wiping alone doesn’t clear them, run an old toothbrush or piece of dental floss between the teeth to dislodge anything stuck. You want the comb completely clear before each new pass so you can see exactly what’s coming out of the hair.
Sanitize With Hot Water After Each Session
Once you’ve finished combing, the comb needs a proper sanitizing soak. The CDC recommends submerging combs and brushes in water that’s at least 130°F for 5 to 10 minutes. That temperature is well above the threshold that kills lice within minutes. For reference, 130°F is hotter than most tap water but not boiling. You can heat water on the stove or use the hottest setting on your tap and verify with a kitchen thermometer.
Temperatures above about 122°F (50°C) are lethal to lice within minutes, so 130°F with a 5 to 10 minute soak provides a comfortable safety margin. You don’t need to boil the water, and in fact boiling (212°F) could warp or damage plastic lice combs, especially cheaper ones with precisely spaced teeth. If the teeth bend or spread even slightly, the comb becomes less effective at trapping nits.
Alternative Cleaning Methods
If you can’t heat water right away, you have a couple of backup options. Soaking the comb in a solution of dish soap and very warm water for 10 minutes will help loosen debris and drown any active lice, though it’s not as reliable for killing nits. For a more thorough disinfection without heat, soaking in rubbing alcohol (70% isopropyl) for 10 minutes is another common approach.
The simplest alternative requires no special supplies at all: lice die within about two days without access to a human host. If you seal the comb in a plastic bag and leave it untouched for 48 hours or more, anything on it will be dead. This works as a backup but isn’t practical if you need the comb again the next day for follow-up sessions.
How Often to Clean
Clean the comb after every single combing session, not just after the first one. Most lice treatment plans involve combing every few days for two to three weeks to catch any newly hatched lice before they mature. Each session is a chance for the comb to pick up live lice or viable eggs, so the hot water soak should happen every time.
If multiple people in the household are being checked or treated, sanitize the comb between each person. Sharing a comb without cleaning it in between can transfer lice from one head to another, which defeats the purpose entirely.
Metal vs. Plastic Combs
Metal lice combs with rigid, closely spaced teeth handle hot water soaks better than plastic ones. They won’t warp at 130°F, they’re easier to wipe clean between passes, and the teeth stay uniformly spaced over time. If you’re using a plastic comb that came packaged with a lice treatment kit, it will survive the recommended 130°F soak, but inspect the teeth periodically for any bending or spreading. A comb with gaps wider than they should be will miss nits.
Whichever type you use, hold it up to the light after cleaning and make sure nothing is lodged between the teeth. Nits are tiny, oval shaped, and can be the same color as the comb material, making them easy to overlook.