Does HC Red No. 7 Dye Cause Side Effects?

HC Red No. 7 is a synthetic hair dye used in temporary or semi-permanent hair coloring products. The “HC” is for “hair color.” You might also hear people refer to it as Red Dye No. 7 or simply Red Dye 7.

If you color your hair with a product containing HC Red No. 7, you might wonder if it can affect your health. This article addresses that question.

What Is HC Red No. 7?

HC Red No. 7 is a chemical compound used in many industries, including the manufacturing of hair dyes, highlighting products, color shampoos and rinses. It primarily coats the outer layer of hairs rather than penetrating deeply, as some other compounds do.

As a result, it’s less permanent and typically washes out after several shampoos. That’s why it’s a popular choice with people wanting to experiment with red coloring without committing to a long-term change.

Red Dye 7 is generally considered safe when used as intended. Still, it’s essential to understand its possible side effects.

Potential Side Effects From HC Red No. 7

While HC Red No. 7 is considered relatively safe, some people experience adverse effects when exposed to it, including:

• Skin irritation. It can irritate the skin, especially with more prolonged exposure. People with sensitive skin are more likely to experience irritation.
• Allergic reactions. Sensitive individuals may experience more significant reactions, including contact dermatitis with redness, itching, burning or a rash on the scalp or elsewhere. Allergic reactions to any substance can also manifest as swelling, hives or even respiratory distress.
• Eye irritation. If HC Red No. 7 gets into your eyes, you may experience burning and redness.
• Hair damage. While semi-permanent dyes are less damaging than permanent ones, frequent use can cause hair dryness and brittleness.

People who work with HC Red No. 7 or use it to color their hair may be concerned about whether it increases cancer risk. The Cosmetic Ingredient Review (CIR) Expert Panel evaluated scientific studies and concluded that the substance is safe when used in the appropriate concentrations. Nevertheless, following safe practices for handling HC Red No. 7 or having it applied to your hair is critical.

Tips for Using HC Red No. 7

You can reduce the risk of adverse reactions or side effects from HC Red No. 7 by doing the following:

• Test it first. Apply a small amount of the dye to your skin in an inconspicuous area (like behind your ear) and check periodically over 24 to 48 hours for a reaction.
• Follow the manufacturer’s instructions. Whether you apply the dye yourself or have a professional do it, using the product as directed is crucial.
• Let your scalp recover between applications. It’s best to limit the frequency of exposure to HC Red No. 7, giving your hair and scalp time to recover between applications.
• Minimize scalp contact. Try to limit your scalp’s direct exposure to HC Red No. 7 when it’s being applied.

Talk With Your Baptist Health Doctor About Red Dye 7

HC Red No. 7 is generally considered safe when used as directed. Still, if you have questions or concerns about its side effects, your doctor can answer them or refer you to a dermatologist.

If you don’t have a Baptist Health physician, you can find one in our online provider directory.

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