Left index finger tip palm side especially itchy, there are many reasons, common ringworm, eczema, contact dermatitis, insect bite dermatitis and so on. 1. Ringworm: fungal infection caused by ringworm, may lead to the left index finger tip palm side especially itchy, may also be accompanied by peeling skin, blisters and other symptoms. 2. Eczema: internal and external stimulation of a variety of factors causing inflammatory skin reactions, occurring in the fingers, may also appear on the left index finger tip palm side especially itchy, accompanied by local erythema, scales and other changes. 3. Contact dermatitis: contact dermatitis caused by finger tips coming into contact with external sensitizers can also occur on the palmar side of the left index finger tip, especially itchy. 4. Insect bite dermatitis: local mosquito bites may also lead to the left index finger tip of the palm side of the special itch. Left hand index finger tip palm side especially itchy, there may be other reasons, it is recommended to go to the hospital to check the cause.