How long should dichlorvos be left when killing lice? - briefly
Apply dichlorvos as directed and keep it on the scalp for roughly 10‑15 minutes before rinsing. Do not exceed the label‑specified exposure time to prevent toxicity.
How long should dichlorvos be left when killing lice? - in detail
Dichlorvos (DDVP) is a fast‑acting organophosphate insecticide commonly used for lice eradication. Effective control depends on maintaining the recommended contact period after application. Manufacturers typically advise a minimum exposure of 5–10 minutes on the scalp and hair before rinsing. Extending the time to 15 minutes can increase mortality of both adult lice and nymphs, especially in heavy infestations, but longer exposure raises the risk of skin irritation.
Key parameters for optimal results:
- Concentration: Use the product’s labeled strength; diluting below the indicated level reduces efficacy, while concentrating beyond the label is unsafe.
- Application method: Apply the solution evenly, ensuring saturation of hair shafts and scalp skin. Use a fine‑tooth comb to distribute the liquid throughout the hair mass.
- Contact duration: Keep the liquid on the scalp for at least 5 minutes. For severe cases, allow up to 15 minutes, then rinse thoroughly with warm water.
- Rinsing: Remove all residue with copious water; a mild shampoo may be employed after the rinse.
- Post‑treatment: Repeat the procedure after 7–10 days to target any newly hatched lice that survived the initial exposure.
Safety considerations:
- Avoid contact with eyes, mucous membranes, or broken skin.
- Do not apply to children under 2 years of age or to pregnant or nursing individuals unless directed by a healthcare professional.
- Use gloves and ventilate the area during application.
- Store the chemical out of reach of children and pets.
If irritation, excessive redness, or respiratory symptoms develop, wash the area immediately and seek medical advice. Proper adherence to the specified exposure time, concentration, and safety measures ensures maximum lethality against lice while minimizing adverse effects.