Management of relapsing-remitting MS
In the United States, as of 2005 there are five FDA-approved treatments for patients with relapsing-remitting MS. Three are interferons: Interferon beta-1a (Avonex and Rebif) or beta-1b (Betaseron [in Europe Betaferon]). The interferons are medications derived from human cytokines which help regulate the immune system. A fourth medication is glatiramer acetate (Copaxone), a mixture of polypeptides which may protect important myelin proteins by substituting itself as the target of immune system attack. The final medication, mitoxantrone is effective but is limited by cardiac toxicity. All five medications have been proven to be modestly effective at decreasing the number of attacks and slowing progression to disability. They differ primarily in ease of use, price, side effects, and the likelihood that extended use will decrease their effects. All of these therapies are expensive and require frequent injections, with Avonex requiring weekly injections and Copaxone daily injections. All of the interferons can lose effectiveness after continued use, with Avonex being the least likely and Betaseron the most likely. This is the result of neutralizing antibodies against the interferons. The interferons all require laboratory monitoring of blood tests. Even with appropriate use of medication, most patients with relapsing-remitting MS still suffer from some attacks and subsequent disability. Side effects are covered below.

Management of progressive MS
Treatment of progressive MS is more difficult than relapsing-remitting MS, and many patients do not respond to any therapy. A wide range of medications have been used to try to slow the progression of disease. Many therapies have been shown to have some effect on disease progression and resulting disability, but most therapies have significant side effects which limit their long-term use. Therefore they are often appropriate only for the most rapidly progressive cases. Azathioprine, cladribine, and cyclosporine have all shown small benefits, which in most cases are outweighed by side effects such as an increased cancer risk. Mitoxantrone, a chemotherapy drug, offers a significant reduction in progression to disability, but causes dose-dependant cardiac toxicity which limits its long-term use. Natalizumab (marketed as Tysabri) showed promise in early trials but has been withdrawn from the market in the United States because of an association with progressive multifocal leukoencephalopathy. Bone marrow transplant, plasmapheresis, and total lymphoid irradiation (exposure to high doses of radiation in order to kill parts of the immune system) have been studied and are currently reserved for the most dire cases. Cyclophosphamide and methotrexate are chemotherapy drugs which can slow the progression of MS, but which also have a number of side effects. Frequent courses of high-dose corticosteroids, often given weekly or monthly, are also commonly employed to good effect. Interferons show promise in secondary progressive MS, but more data is needed to support widespread use.

Management of demyelination without a diagnosis of MS
Several studies have shown that starting treatment with interferon beta-1a during the initial attack (and prior to the second attack required for a definite diagnosis of MS) can decrease the chance that a patient will develop MS. A separate medication, intravenous immunoglobulin (IVIG) has also shown promise in reducing progression to MS in this set of patients. Therefore, in certain patients, it is important that therapy be started prior to definite diagnosis.

Management of the effects of MS
Because much of the damage caused by MS is irreversible, management of the resulting deficits is very important. As for any patient with neurologic deficits, a multidisciplinary approach is key to limiting and overcoming disability. Physical therapy, occupational therapy, and orthopedic instruments (e.g., wheelchairs, standing frames) may be helpful.speech therapy is also an important component to a comprehensive approach to maintaining quality of life. Treatment of emotional distress and depression should involve mental health professionals such as therapists, psychologists, and psychiatrists. Neurocognitive testing is important for determining the extent of cognitive deficits. Management of cognitive defects relies on lifestyle strategies, but also may respond to donepezil. Medications such as baclofen, tizanidine, dantrolene and Sativex have been shown to improve spasticity. Depression can be treated with a variety of antidepressants; selective serotonin reuptake inhibitors (SSRIs) are most commonly employed. The anticonvulsant drugs gabapentin and carbamazepine and the antidepressant amitriptyline can improve pain and tingling sensations in certain cases. Fatigue can often be managed by amantadine, pemoline, methylphenidate, and modafinil. Bladder spasms can be treated by oxybutynin and trospium chloride. Erectile dysfunction may respond to sildenafil, vardenafil, or tadalafil.