Head lice infestations are common, and treating the hair is only half the battle against these parasites. Brushes, combs, and other hair accessories can harbor live lice and their eggs, known as nits, leading to re-infestation after successful head treatment. The goal of brush disinfection is to eliminate both the adult insects and the nits to break the reproductive cycle entirely. Cleaning your grooming tools is a practical measure in fully clearing an infestation.
Preparing the Tools for Treatment
Before beginning any disinfection method, it is important to physically clear the tools of all hair and debris. Lice and nits can easily cling to or hide within strands of shed hair, lint, and product residue trapped in the bristles. Removing this material ensures that the subsequent chemical or thermal treatments can fully contact all surfaces of the brush.
Use a fine-toothed comb, a pair of tweezers, or even a small pair of scissors to thoroughly cut away or pull out all visible debris. This initial step is necessary because any remaining hair acts as a barrier, potentially shielding a louse or nit from the disinfectant. Once the brush is visibly clean, it is ready for one of the active killing methods.
High-Heat and Chemical Disinfection
One of the fastest and most effective ways to kill lice and nits is through exposure to high heat. Lice are known to die after only five minutes of exposure to temperatures at or above 130°F (54°C). To achieve this, you can bring a pot of water to a rolling boil and then remove it from the heat before submerging the brushes for a minimum of 10 minutes.
Boiling water can warp or melt many plastic brushes and combs, especially those with synthetic materials. For items that cannot withstand extreme heat, chemical soaking provides an alternative. Submerge the brushes for up to an hour in a solution of the pediculicide shampoo used on the hair, or a 70% concentration of isopropyl alcohol. A longer soak ensures the chemical fully penetrates hard-to-reach areas and kills resilient nits.
Isolation and Cold Treatment Options
For delicate, expensive, or non-washable grooming tools, methods relying on temperature extremes or time are suitable alternatives to heat or chemical saturation. Lice must feed frequently on human blood and will perish if separated from a host for a sufficient duration. Sealing the tools completely in an airtight plastic bag, such as a zip-top bag, is an effective isolation method.
While adult lice typically die within 24 to 48 hours off the head, a longer isolation period is recommended to account for nits that may hatch later. Sealing the bag and storing it away for a minimum of two weeks ensures that any surviving nits hatch and the newly emerged nymphs die without a blood meal. Alternatively, use cold temperatures by placing the sealed bag of brushes into a deep freezer for at least 12 hours, or ideally overnight, to kill both the lice and the nits. Once treatment is complete, keep the clean tools separated from any others until the entire infestation has been cleared from the household.