Dry and itchy armpits may be caused by ringworm, chronic eczema and pruritus. 1. Ringworm: fungal infection caused by ringworm, may cause skin ring-like erythema, flaking, itching, can also lead to dry and itchy armpits. 2. Chronic eczema: internal and external stimulation of a variety of factors causing inflammatory skin reactions, chronic eczema can lead to mossy skin, dry skin, cracking, itching, can also cause dry and itchy armpits. 3. Pruritus: the etiology is complex, and dry skin, mental factors, systemic diseases, can lead to itchy skin, even if there is no primary skin damage, can also lead to dry and itchy armpits. Dry and itchy armpits, there may be other reasons, you need to go to the hospital in time to check and clarify the cause.