Dr. Lekutat's answer:

It’s always tempting to scratch an itch. But when it’s your ear that’s itching, the impulse to scratch can be dangerous – especially if you insert objects such as cotton swabs into your ear. Despite what many people believe, you should never insert a cotton swab into your ear – you could even puncture your eardrum, or push earwax deeper into your ear canal. Often itchy ears are caused by infections, which can be worsened if you tug or pull at your ear. If you often suffer from itchy ears, it’s best to pay a visit to a doctor or ENT. They’ll diagnose the problem and prescribe the proper treatment.