You're looking for vitamins that can help with an acidic rash! Here are three vitamins that may be beneficial:

1. **Vitamin C**: Vitamin C is a powerful antioxidant that can help reduce inflammation and oxidative stress, which can contribute to the development of acidic rashes. Foods rich in vitamin C include citrus fruits, berries, and leafy greens. You can also consider taking a vitamin C supplement.
2. **Vitamin E**: Vitamin E is another antioxidant that can help soothe and calm the skin, reducing inflammation and irritation. Food sources of vitamin E include nuts, seeds, and vegetable oils. You can also take a vitamin E supplement or apply topical creams or oils rich in vitamin E to the affected area.
3. **Vitamin B7 (Biotin)**: Biotin is a B-complex vitamin that plays a crucial role in skin health. It helps to strengthen the skin's barrier function, reducing the risk of irritation and inflammation. Food sources of biotin include eggs, nuts, and whole grains. You can also take a biotin supplement or apply topical creams or oils rich in biotin to the affected area.

In addition to these vitamins, it's essential to maintain a balanced diet that includes a variety of whole foods rich in essential nutrients, such as:

* Omega-3 fatty acids: Found in fatty fish, flaxseeds, and chia seeds, these healthy fats help reduce inflammation and promote skin health.
* Zinc: Found in oysters, beef, and chicken, zinc is essential for wound healing and skin health.
* Probiotics: Found in fermented foods like yogurt and kefir, probiotics help maintain a healthy gut microbiome, which is linked to overall skin health.

Remember to consult with a healthcare professional before taking any supplements or making significant changes to your diet. They can help you determine the best course of treatment for your specific needs.

In the meantime, here are some home remedies you can try to help soothe an acidic rash:

* Apply aloe vera gel or coconut oil to the affected area.
* Take a warm bath with oatmeal or baking soda to help neutralize the skin's pH.
* Use a gentle, fragrance-free soap and shampoo to clean the affected area.
* Apply a moisturizer or barrier cream to protect the skin from further irritation.

Remember to always patch test any new products or ingredients on a small area of your skin before applying them to the affected area.
You're looking for a treatment for an acidic rash! Here are three common treatments that can help:

1. **Topical corticosteroids**: Over-the-counter (OTC) hydrocortisone cream or prescription-strength corticosteroids can help reduce inflammation and itching. Apply a thin layer to the affected area 2-3 times a day.
2. **Cool compresses**: Apply a cool, wet compress to the affected area for 15-20 minutes, several times a day. This can help reduce itching, swelling, and discomfort.
3. **Mild antihistamines**: If the itching is severe, an OTC antihistamine like diphenhydramine (Benadryl) or chlorpheniramine (Chlor-Trimeton) can help relieve itching and reduce the risk of scratching the skin.

Additionally, you can try the following:

* Avoid irritants that may be causing the rash, such as certain soaps or detergents.
* Wear loose, breathable clothing to reduce friction and irritation.
* Apply a barrier cream or moisturizer to protect the skin from further irritation.
* Consider using a gentle, fragrance-free soap and shampoo to clean the affected area.

If your rash persists or worsens, or if you experience fever, difficulty breathing, or swelling of the face, lips, tongue, or throat, seek medical attention.

Remember to consult with a healthcare professional for further guidance and treatment if your symptoms don't improve or if you have concerns about your rash.