I was at work and my arm started itching looked down covered in red bumps they hurt are slowly moving up what could be?

There are several possible causes for red, itchy bumps on the arm that move slowly upward. Here are a few potential explanations:

1. Insect Bites or Stings: If you were in an area with insects, such as mosquitoes, fleas, or wasps, you may have been bitten or stung. Insect bites and stings can cause localized inflammation, redness, itching, and swelling. In some cases, the bumps may move up the arm as the venom or saliva spreads through the skin.

2. Allergic Reaction: An allergic reaction to a substance, such as certain plants, foods, or chemicals, can cause red, itchy bumps on the skin. These bumps may appear in clusters or patches and can spread over time. Allergic reactions can be triggered by contact with the allergen (such as touching poison ivy) or by ingestion or inhalation.

3. Contact Dermatitis: Contact dermatitis is a skin condition that occurs when the skin comes into contact with an irritant or allergen. This can cause redness, itching, and bumps or blisters on the skin. Common irritants and allergens include soaps, detergents, cosmetics, jewelry, and certain plants.

4. Hives (Urticaria): Hives are red, itchy, raised bumps on the skin that can appear suddenly and spread quickly. Hives are often caused by an allergic reaction, but they can also be triggered by stress, heat, or certain medications.

5. Shingles: Shingles is a viral infection caused by the varicella-zoster virus, which is the same virus that causes chickenpox. Shingles typically causes a painful rash of red, itchy blisters that may appear on the arm or other areas of the body. The rash can move upward as the infection spreads.

6. Cellulitis: Cellulitis is a bacterial skin infection that can cause redness, swelling, warmth, and pain in the affected area. The infection can spread quickly and may move up the arm or other parts of the body. Cellulitis requires prompt medical treatment to prevent serious complications.

If you are experiencing red, itchy bumps on your arm that are moving upward, it is important to seek medical attention for proper evaluation and diagnosis. The healthcare provider can determine the cause of the bumps and recommend the appropriate treatment. In some cases, prescription medications or further tests may be necessary.