Photodynamic therapy is a new technology in modern medicine. At present, photodynamic therapy is not yet reimbursed by medical insurance. The drugs applied are about 800 yuan each. Generally, patients with warts that are not very large in size use 1 unit per treatment. If you have a large area, the dosage will be increased. The dosage varies depending on the area of the lesion, usually 1 to 3 sticks are needed each time. In addition, there is also the cost of light, the cost of each photodynamic treatment is calculated in 2000 ~ 3000 yuan. It takes about 3 hours to apply the drug each time and about half an hour of light, so a course of treatment should be done at least 3~5 times. Compared to traditional treatment, the price of this new technology is high, but its advantage is that it is more effective in treating subclinical infections and has fewer side effects. The actual fact is that you can find a lot of people who are not able to get a good deal on a lot of things. There are three elements to photodynamic therapy: photosensitizer, light and oxygen. When the photosensitizer is applied to the human tissue, it will gather in the wart tissue and then irradiate the wart with specific wavelengths of light, the photosensitizer gathered in the wart will produce singlet oxygen and/or free radicals, oxidizing and destroying various biological macromolecules in the tissue and cells, causing irreversible damage to the abnormal proliferation of active cells and eventually leading to abnormal cell necrosis and apoptosis. In short, the photosensitizer only gathers on the “bad cells” and makes the “bad cells” die after light exposure. Moreover, the photosensitizer will be metabolized by the body quickly after application and will not cause any damage to normal skin. Who can’t choose photodynamic therapy? Since photodynamic therapy is so safe and effective, is it an option for all patients? The answer is no. Most patients have no problem choosing photodynamic therapy, however, if they have porphyria (a metabolic disorder caused by the lack of certain enzymes or reduced enzyme activity in the body during heme synthesis), allergy to porphyrins, or skin photoallergy, they cannot use the therapy because the skin of these patients is allergic to light. In addition, pregnant and lactating women, lacking data support from clinical trials, are not advocated for use. Photodynamic therapy is best used in the second treatment phase There are advantages and disadvantages to any treatment modality, and this is also true for photodynamic therapy. Because it is currently the only treatment that is effective for subclinical infections, it is generally used in the second phase of treatment. In the first stage of treatment, the warts are relatively large and treatment with photodynamic therapy will take longer, rather than faster than physical or surgical treatment. As for the third stage of treatment, photodynamic therapy is also not recommended, although it can also improve immunity, but the price is also very high. Patients can consolidate the effect and prevent recurrence by strengthening exercise and using immunomodulators appropriately. What should I do if the affected area is painful and itchy after photodynamic therapy? After the photodynamic therapy, many patients will feel pain at the growth site of warts, most of them are normal post-operative reactions. If the pain is not severe, it is recommended to apply compound polymyxin B cream to the affected area to relieve both inflammation and pain. If you still feel pain after using this medication, you can take oral painkillers with it. In addition, a small number of patients will also feel itchy on the affected area, and a little washing is usually sufficient. If washing does not solve the problem, relief can be obtained by taking second-generation antihistamines or by applying antibiotic cream topically.