Exterol ear drops are used to help remove hardened wax from the ear canal. Exterol is suitable for use by adults, children and the elderly. The active ingredient is urea hydrogen peroxide. It works by breaking down the ear wax into small pieces. Excessive, hardened ear wax is quite common. It causes problem when it builds up and blocks the ear canal. The first symptom is usually a feeling of discomfort and fullness in the ear. This can become painful and cause dizziness and some loss of hearing if left untreated.