To prevent recurrence of erythema nodosum, the following aspects need to be noted: 1. Effective drugs need to be selected for a full course of treatment. You can take oral anti-malarial drug hydroxychloroquine sulfate tablets, or choose aminophenone tablets or thalidomide tablets to achieve anti-inflammatory and immunomodulatory treatment; if accompanied by pain in joints, you can take oral rehmannia multi-glucoside tablets or Kunxian capsules to enhance pain relief and immunomodulatory treatment. In terms of topical medication, you can apply Denide ointment or Mometasone furoate ointment. Usually, after the rash has completely subsided, oral medication can be taken again for a period of time for scientific reduction to reduce the chance of recurrence. 2. To ensure good rest and reduce the aggravation of erythema nodosum caused by excessive walking.