What is the cause of top external ear to itch with hard a bumb under each ear?

Causes of Ear Itching and Bumps:

1. Dermatitis: Eczema, psoriasis, and other skin conditions can cause itching, redness, and scaling of the skin, including the ear.

2. Allergic reactions: Allergies to substances like pollen, dust, pet dander, or cosmetics can cause itching and inflammation of the skin, including the ears.

3. Earwax Buildup: Excessive earwax can cause itching, a feeling of fullness in the ear, and decreased hearing.

4. Otitis Externa (Swimmer's Ear): A bacterial or fungal infection of the outer ear canal, often caused by prolonged exposure to water or trauma to the ear. Symptoms include itching, pain, discharge, and hearing loss.

5. Insect Bites or Stings: Bites from insects like mosquitoes, spiders, or fleas can cause itching, redness, and swelling around the ear.

6. Contact Dermatitis: A reaction to substances that come into contact with the skin, such as jewelry, hair products, or soaps, can cause itching, redness, and a bumpy rash.

7. Shingles (Herpes Zoster): A viral infection that causes a rash of small, painful blisters. It can affect the ear and surrounding areas, causing itching and blisters.

8. Seborrheic Dermatitis: A common skin condition that affects oily areas of the skin, including the scalp, face, and ears. It can cause itching, redness, and scaling.

9. Folliculitis: Inflammation or infection of the hair follicles, which can cause itchy, red bumps on the skin.

10. Tumors or Cysts: In rare cases, itching and bumps around the ear could be a sign of an underlying medical condition, such as tumors or cysts.

If you have persistent itching and bumps on the outer ear, especially accompanied by other symptoms like ear pain, discharge, or hearing changes, it's essential to consult a healthcare professional for proper diagnosis and treatment. They can determine the underlying cause and recommend the appropriate treatment options to relieve itching and address any underlying medical conditions.