Inflammatory and hair loss conditions of the scalp are rare but can also cause itching.

CNN: Why is my scalp so itchy?

Inflammation of the hair follicles or bacterial infection of the scalp can also cause itching.

CNN: Why is my scalp so itchy?

They can grow to be large and cosmetically unsightly, but typically are painless or cause only itching or burning (in 20 percent).

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The worm can also cause severe itching under the skin, and it is hoped that cases can be reduced to only a fraction of previous levels.

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Systemic, or whole body, diseases can sometimes cause scalp itching.

CNN: Why is my scalp so itchy?

Many treatments for acne cause redness, itching and irritation, which make it difficult to continue using them.

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The side effects from the medicine can also be nasty: Ivermectin may cause fever, itching, skin rash, joint or muscle pain, rapid heartbeat, and painful, tender glands.

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Itching may be severe, and scratching the rash can make it even itchier and cause more inflammation.

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An estimated 16% of U.S. adults are infected with herpes simplex virus type 2 (HSV-2), which can cause bumps, blisters, or sores on the genitals and surrounding areas, along with pain and itching.

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