After applying the corn plaster for several days, the surrounding area turned white, but the corn hasn't come out.

After applying corn plaster for several days, the surrounding area may turn white, but the corn has not come out. This could be due to incorrect usage, insufficient treatment duration, or a more severe condition. Different causes require different treatments. Specific explanations are as follows:

1. Incorrect usage

Under normal circumstances, corn plasters should be changed every 3–5 days. Before each change, residual medication must be thoroughly removed. If these steps are not followed, the treatment may be ineffective, leading to the corn not being fully removed. Therefore, it is essential to use the corn plaster correctly to achieve the desired therapeutic effect.

2. Insufficient treatment duration

Corn plaster is a topical medication that works by softening and gradually removing thickened skin layers through mild corrosion. If used for too short a period, it may fail to produce satisfactory results. It is important to follow medical advice when using such treatments and avoid self-medicating without professional guidance.

3. Severe condition

If the corn is particularly severe, there may be little noticeable improvement even after several days of using corn plaster. In such cases, alternative treatments such as cryotherapy (freezing) or laser therapy may be recommended. These methods can freeze, damage, and ultimately cause the necrotic tissue and keratin plug to fall off.

If other discomforts or symptoms occur, patients are advised to seek timely medical attention at a hospital for accurate diagnosis and appropriate treatment.