Fungal infections can be detected after applying ointment, but it may affect the accuracy of the test. Fungus is parasitized on the skin, not only on the surface of the skin, but also in the deeper parts of the skin, and the application of ointment can only kill the fungus on the surface of the skin, and the examination can usually detect the fungus in the deeper parts of the skin, so it can be detected even if the ointment is applied. In addition, it takes time for the ointment to work, and if you just start using it, the effect of the ointment has not been fully realized, and there will still be residual fungus on the surface of the skin, which can also be detected by a fungal examination at this time. Although the ointment can be detected, it is generally not recommended to apply the ointment before the examination, because the fungal examination usually includes methods such as fungal microscopy and fungal culture, and applying the ointment may affect the quality of the specimen, which may cause the examination results to be biased, so it is generally recommended to do the examination after one week if the ointment has been applied. In case of fungal infection, it is necessary to go to the hospital in time and follow the doctor’s instructions for better treatment of the disease.