How should dichlorvos be used for lice? - briefly
Apply dichlorvos as a 0.1% solution directly to the infested hair, ensuring full coverage, leaving it on for the label‑specified duration, then rinse thoroughly; perform the procedure in a well‑ventilated area while wearing gloves and eye protection.
How should dichlorvos be used for lice? - in detail
Dichlorvos, an organophosphate compound, is employed as a contact insecticide for lice eradication in controlled environments. The product is available in liquid concentrate, aerosol spray, and impregnated strip formats; each requires specific handling to achieve effective pest control while minimizing toxic exposure.
The liquid concentrate must be diluted according to the manufacturer’s instructions, typically to a 0.5‑2 % solution. Use a calibrated measuring device to achieve the exact concentration. Apply the solution uniformly to the affected area with a spray bottle or sponge, ensuring complete wetting of hair and scalp. Allow the preparation to remain on the surface for 10–15 minutes before rinsing thoroughly with water. For aerosol formulations, maintain a distance of 30 cm from the scalp, dispense a fine mist to cover the entire head, and observe the same exposure interval before washing.
Protective equipment is mandatory: wear nitrile gloves, a disposable gown, and eye protection. Perform the procedure in a well‑ventilated room; open windows and use an exhaust fan to disperse vapors. Keep the chemical away from food, drink, and open wounds. After application, wash hands and any exposed skin with soap and water. Store the concentrate in a locked cabinet, away from children and pets, at temperatures below 30 °C.
Pre‑treatment steps include combing out visible nits with a fine‑toothed lice comb to reduce the mechanical load. After chemical exposure, rinse the hair with warm water, then dry with a clean towel. Repeat the treatment after seven days to target any newly hatched lice that escaped the initial dose. Do not exceed two applications within a 14‑day period, as cumulative toxicity may increase.
Environmental decontamination involves laundering bedding, clothing, and hats at 60 °C or higher, or sealing non‑washable items in a plastic bag for at least 48 hours. Dispose of used applicators and gloves in a sealed container; follow local hazardous waste guidelines for disposal of residual solution.
Contraindications include use on infants under six months, pregnant or nursing individuals, and persons with known sensitivity to organophosphates. Symptoms of overexposure—such as headache, dizziness, excessive salivation, or muscle twitching—require immediate medical attention and decontamination.
Regulatory agencies in many regions restrict dichlorvos to professional pest‑control operators; over‑the‑counter use for human lice is often prohibited. Safer alternatives, such as dimethicone‑based lotions or prescription pediculicides, are recommended when available.