If you suspect that you may be allergic to hyaluronic acid, there are a few signs and symptoms you can look out for:

1. Skin irritation: Allergic reactions to hyaluronic acid may manifest as redness, itching, or a rash on the skin. This can occur immediately after applying a product containing hyaluronic acid or may develop over time with continued use.

2. Swelling or puffiness: In some cases, an allergic reaction to hyaluronic acid may cause swelling or puffiness in the area where the product was applied. This can be particularly noticeable around the eyes or lips.

3. Dryness or tightness: Allergic reactions can disrupt the skin's natural moisture barrier, leading to dryness or tightness. If you notice these symptoms after using a product containing hyaluronic acid, it could be a sign of an allergic reaction.

4. Bumps or hives: Allergic reactions may also present as small raised bumps or hives on the skin. These can be itchy and may spread beyond the area where the product was applied.

It's important to note that while allergic reactions to hyaluronic acid are possible, they are relatively rare. Hyaluronic acid is generally well-tolerated by most people and is considered safe for use in skincare products. However, if you experience any of the above symptoms after using a product containing hyaluronic acid, it's best to discontinue use and consult with a dermatologist or allergist for a proper diagnosis. They can perform patch tests or other diagnostic tests to determine if you are indeed allergic to hyaluronic acid or if there might be another ingredient causing the reaction.