1.What is maintenance therapy? Maintenance therapy first originated from clinical experience in the treatment of tuberculosis, and was later expanded in oncology, organ transplantation, rheumatology and other applications. Maintenance therapy refers to the treatment measures taken to prevent relapse of the disease when the patient is in complete remission, partial remission or stable disease after receiving intensive treatment. Maintenance therapy can be either the same drug used in intensive therapy or another drug. Whether one or two drugs are used in combination depends on the doctor’s clinical experience and the patient’s specific physical condition (treatment effect, adverse effects, cost). 2.Why should I take maintenance treatment mode? Demyelinating disease is an autoimmune disease occurring in the central nervous system and has common features of other autoimmune diseases, which are chronic, fluctuating, difficult to cure, and prone to relapse and progression after stopping treatment. The end result of recurrent attacks leads to severe disability and even life-threatening conditions in patients. Therefore, the purpose of maintenance therapy is to control disease fluctuations, prevent relapses, and improve quality of life. Maintenance therapy is common and recognized in the fields of oncology, organ transplantation, rheumatology, etc. There is no objection to maintenance therapy for hypertension and diabetes. However, in the clinical practice of neurological immune diseases such as multiple sclerosis and optic neuromyelitis optica, maintenance therapy is applied less frequently, especially the use of corticosteroids, which is limited to a maximum of 3 weeks by foreign guidelines. In clinical work, we often encounter patients with relapses with hormone shock therapy, short-term oral hormone therapy, remission and then discontinuation. Then relapse and use the drug again. Less than two years after the onset of the disease, the body has been left with serious disabilities, such as bilateral lower limbs or even quadriplegia, uncontrollable urination and defecation, and blindness in one or both eyes. Even with further aggressive treatment, the basic state of self-care cannot even be restored. Experience and lessons learned suggest that patients should not lose the best window of time for treatment at the early stage of the disease, allowing one relapse, avoiding two relapses, and eliminating three relapses. For this reason, maintenance treatment mode should be adopted. 3.What kind of drugs are suitable for maintenance treatment? At present, there are 3 kinds of 8 drugs approved by the U.S. Food and Drug Administration for multiple sclerosis. Four interferons, one monoclonal antibody, one chemical drug and two synthetic ones. Only two interferons and one chemical drug are available in China. Foreign clinical trial data suggest that long-term use of interferon drugs and antibody drugs can partially reduce the annual recurrence rate and improve or stabilize the disability status. However, relapses still occur after discontinuation of use. The biggest problem is the cost required for long-term use, which is difficult for many families to support. The immunosuppressant mitoxantrone can be used in the treatment of multiple sclerosis, but the cumulative dose should not exceed 140 mg/person, and the duration of administration is mostly two years. Other immunosuppressants can be seen in studies and are not recognized by everyone. In addition, interferon may not be suitable for the treatment of optic neuromyelitis optica. After nearly 30 years of clinical accumulation, we believe that whether it is multiple sclerosis, or optic neuromyelitis optica low-dose hormone and other immunosuppressants such as cyclophosphamide, azathioprine, methotrexate, etc. have been clinically used for half a century, and the adverse effects are well known to everyone, and should be the first-line drugs of clinical preference. 4.How to choose the appropriate maintenance therapy drugs? The ideal maintenance drug should be single agent, sensitive and effective, with no or mild adverse effects, low cost, and convenient for long-term use. Specifically for patients with demyelinating diseases, hormones are sensitive and effective for the majority of patients, with low cost and long-term use although there are a variety of adverse effects. However, the occurrence of adverse reactions is related to the physical condition of the patient. We encountered a patient who had been taking hormones for up to 30 years without significant secondary bone damage and without diabetes or hypertension. Of the nearly 80 patients treated, only four (5%) developed bone changes. For hormone-insensitive patients, the “good value” methotrexate and azathioprine are also options, and the combination is even better. Methotrexate is more expensive and can be considered by patients with financial conditions. 5.How to prevent and deal with the possible adverse reactions of drugs in maintenance therapy? ”It is a medicine with three toxins”. Long-term use of drugs will certainly produce adverse reactions. We can neither choke nor rely on God by chance. Start with a small dose and titrate the optimal therapeutic dose of the drug according to the patient’s physical response. And take precautions against possible adverse reactions to the drug. For potential adverse reactions, check weekly at the beginning of the medication, such as liver and kidney function, blood routine, blood sugar, etc. If there is no abnormality, regular (1-3 months) check after six months. When adverse reactions occur, implement symptomatic treatment, or discontinue the drug, or change the drug. Long-term use of drugs reduces the sensitivity and efficacy of drugs, and advocates the use of small doses of combined drugs. 6.How long is the “maintenance” period of maintenance therapy? There is no best answer. Most people choose to discontinue maintenance therapy for at least 3-4 years after no recurrence for anti-epilepsy and antipsychotic. For lifelong medications such as diabetes, hypertension, and hyperlipidemia, we have patients who have relapsed in the 5th year of maintenance therapy. Thus, the principle of individualization of medication is recommended, i.e. according to the patient’s lesion and physical condition.