There are four main types of multiple sclerosis (MS) and relapsing-remitting multiple sclerosis (RRMS) is the most common. It’s also the type most people receive as a first diagnosis.

There are currently 20 different drugs approved by the Food and Drug Administration (FDA) to prevent the brain and spinal cord damage that leads to MS symptoms. These are often referred to as “disease-modifying drugs” because of their ability to slow MS from getting worse.

As you start on your first MS treatment, here are a few things you should know about the medications for RRMS, how they can help you, and what side effects they might cause.

Before you go home with a new treatment plan, here are a few questions to ask your doctor:

  • Why are you recommending this treatment?
  • How will it help my MS?
  • How do I take it? How often do I need to take it?
  • How much does it cost?
  • Will my health insurance plan cover the cost?
  • What side effects could it cause and what should I do if I have side effects?
  • What are my other treatment options, and how do they compare to the one you’re recommending?
  • How long should it take before I can expect to notice results?
  • What should I do if my treatment stops working?
  • When is my next appointment?
  • What are the signs that I should call you in between scheduled visits?

Everyone’s goals when starting treatment may be a little different. In general, the aim in treating MS is to:

  • reduce the number of relapses
  • prevent the damage that causes lesions in the brain and spinal cord
  • slow the progression of the disease

It’s important to understand what your treatment can and can’t do and to be realistic about your goals. Disease-modifying drugs can help reduce relapses, but they don’t prevent them entirely. You may need to take other medications to relieve symptoms when they occur.

Disease-modifying drugs can help slow the formation of new lesions in your brain and spinal cord, and they can also help to reduce relapses. It’s important to start on one of these treatments as soon as possible after diagnosis and to stay on it for as long as your doctor recommends.

Research has found that starting treatment early can help slow the progression of RRMS to secondary-progressive MS (SPMS). SPMS gradually gets worse over time, and it can cause more disability.

Disease-modifying MS treatments come as injections, infusions, and pills.

Injected medicines

  • Beta-interferons (Avonex, Betaseron, Extavia, Plegridy, Rebif) [KW1] are injected as often as every other day or as little as every 14 days, depending on the exact treatment you’re prescribed. Side effects can include flu-like symptoms and injection site reactions (swelling, redness, pain).
  • Glatiramer acetate (Copaxone, Glatopa) is injected as often as every day or up to three times each week, depending on which drug you’re prescribed. Side effects can include injection site reactions.


  • Cladribine (Mavenclad) is a tablet you get in two courses, once a year for 2 years. Each course is made up of two 4- to 5-day cycles, given one month apart. Side effects can include respiratory infections, headaches, and low white blood cell counts.
  • Dimethyl fumarate (Tecfidera) is an oral treatment you start by taking a 120-milligram (mg) capsule twice per day for one week. After the first week of treatment, you’ll take a 240-mg capsule twice per day. Side effects may include flushing of the skin, nausea, diarrhea, and belly pain.
  • Diroximel fumarate (Vumerity) starts with one 231-mg capsule twice per day for 1 week. Then you double the dose to two capsules twice per day. Side effects can include skin flushing, nausea, vomiting, diarrhea, and belly pain.
  • Fingolimod (Gilenya) comes as a capsule that you take once per day. Side effects can include headache, flu, diarrhea, and back or belly pain.
  • Siponimod (Mayzent) is given in gradually increasing doses over 4 to 5 days. From there, you’ll take a maintenance dose once a day. Side effects may include headaches, high blood pressure, and liver problems.
  • Teriflunomide (Aubagio) is a once-daily pill, with side effects that may include headaches, hair thinning, diarrhea, and nausea.
  • Zeposia (Ozanimod) is a once-daily pill, with side effects that can include increased risk of infection and a slowed heart rate.


  • Alemtuzumab (Campath, Lemtrada) comes as an infusion that you get once per day for 5 days in a row. One year later, you get three doses 3 days in a row. Side effects can include rash, headaches, fever, stuffed nose, nausea, urinary tract infection, and fatigue. You won’t typically be prescribed this medication until you’ve tried and failed two other MS drugs.
  • Ocrelizumab (Ocrevus) is given as a first dose, a second dose 2 weeks later, then once every 6 months. Side effects can include infusion reactions, an increased risk of infections, and a possible increased risk for some types of cancer, including breast cancer.
  • Mitoxantrone (Novantrone) is given once every 3 months, with a maximum of 12 doses over 2 to 3 years. Side effects can include nausea, hair loss, upper respiratory infection, urinary tract infection, mouth sores, irregular heart rate, diarrhea, and back pain. Due to these severe side effects, doctors usually reserve this drug for people with severe RRMS that’s getting worse.
  • Natalizumab (Tysabri) is given once every 28 days in an infusion facility. In addition to side effects like headaches, fatigue, joint pain, and infections, Tysabri may increase the risk for a rare and possibly serious brain infection called progressive multifocal leukoencephalopathy (PML).

You will work together with your doctor to develop a treatment plan based on the severity of your disease, your preferences, and other factors. The American Academy of Neurology recommends Lemtrada, Gilenya, or Tysabri for people who experience a lot of severe relapses (called “highly active disease”).

If you do develop side effects, call your doctor for advice. Don’t stop taking the drug without your doctor’s approval. Stopping your medication could lead to more relapses and nervous system damage.

Today there are many different medications available to treat MS. Starting on one of these drugs soon after a diagnosis can help slow the progression of your MS and reduce the number of relapses you get.

It’s important to be an active participant in your own care. Learn as much as you can about your treatment options so you can have a thoughtful discussion with your doctor.

Make sure that you know the potential benefits and risks of each drug. Ask what to do if the treatment you’re taking doesn’t help, or if it causes side effects that you can’t tolerate.