Full Marks Head Lice Solution is a simple treatment that takes approximately 10 minutes to work and is clinically proven to kill head lice quickly. Why use Full Marks Head Lice Solution? Contains cyclomethicone & isopropyl myristate, which cause the lice to to die through dehydration. Eliminates eggs. Fine metal tooth comb included in the pack. Low odour, no traditional pesticides. Suitable from 2 years and over, including those with asthma and sensitive skin