MS Drugs Compared

We don’t have a cure for multiple sclerosis yet. But the FDA has approved more than a dozen drugs that can slow, or “modify,” the course of your MS. They may lessen your symptoms, keep your disease from getting worse sooner, and make relapse attacks less frequent.

You take them in one of three ways: as pills, injections, or infusions into a vein. Some may work better for you than others. They can cause different or different degrees of side effects.

Almost all of the medications are for the most common type of MS, called relapsing-remitting MS (RRMS). Two drugs treat more advanced forms of the disease.

Interferon Beta (Avonex, Betaseron, Extavia, Plegridy, Rebif)

How it works: These are lab-made versions of your body’s infection-fighting protein. They’ve been around the longest and are the most widely prescribed drugs for MS. They’re a type of drug called biologics, which are made with living cells. Doctors aren’t sure, but they think interferon betas turn down signals in your body that trigger the autoimmune response that leads to MS.

How you take them: One injection with a pre-filled autoinjector pen or a syringe every other day or once a week, depending on the drug. Pegylated interferon beta-1a (Plegridy) stays active in your body longer than others, so you take it less often.

Side effects. They can include:

You shouldn’t take these drugs if you have an allergy to interferon beta or albumin, the main protein in blood plasma.

Glatiramer Acetate (Copaxone, Glatopa)

How it works: It’s a lab-made protein that may protect against cells that damage myelin, the protective layer for your nerves. The drug makes relapses happen less often.

How you take it: Injection in the arm, abdomen, hip, or thigh once a day or three times a week, depending on your dose.

Side effects . Serious problems are uncommon, but you may get:

  • Redness, pain, or swelling where the shot went in
  • Flushed skin
  • Shortness of breath
  • Rash
  • Chest pain


Fingolimod (Gilenya)

How it works: This was the first pill approved for MS. It binds to white blood cells and traps them in your lymph nodes so they can’t do damage in your central nervous system. It can help lower the number of MS relapses. It may work about as well as interferon beta, although the evidence is limited.

How you take it: One capsule a day. Because fingolimod can sometimes cause a slower heart rate, your doctor will likely keep close tabs on it, especially when you start.

Side effects: This drug can cause birth defects. You shouldn't take it if you’re pregnant or plan to be. You also may be more likely to get an infection or have swelling in your eyes that can affect your vision. Other issues to watch for include:

Teriflunomide (Aubagio)

How it works . This drug blocks enzymes that activate your white blood cells. This slows down the production of the immune cells that are active when MS is damaging your nerves.

How you take it: One tablet a day.

Side effects : It can cause major birth defects. If you’re pregnant or thinking about getting pregnant, you shouldn’t take it. Your doctor also will need to monitor you closely for any liver, kidney, or nerve damage, as well as infections and high blood pressure. Other issues include:

Cladribine (Mavenclad)

How it works: A disease modifier,  cladribine is for treating relapsing forms of MS including relapsing-remitting disease and active secondary progressive disease. It attacks the part of your blood which is attacking the myelin which protects your nerves.

How you take it: Once a day for five days for the first month. Once a day for five days the second month.

Side effects: 

  • Low white blood count
  • Hair loss
  • Rash
  • Susceptability  to tubercul
  • Mouth sores and/or shigles


Dimethyl Fumarate (Tecfidera)

How it works: Researchers think this pill may block immune cells that damage your nerves. It may also act like an antioxidant to help protect your brain and spinal cord. Doctors have long used it to treat psoriasis, another autoimmune disorder.

How you take it: One capsule twice a day.

Side effects: It can affect your blood counts, so your doctor will check those every few months. You also might have swelling in your throat and tongue, which can make it hard to breathe. You might have some digestive problems, like:

  • Nausea
  • Diarrhea
  • Abdominal pain
  • Flushing, like a hot flash

Alemtuzumab (Lemtrada)

How it works: The FDA approved this powerful, long-lasting drug to treat MS in 2014. It’s a monoclonal antibody, which means it can find and target specific immune cells to keep them from damaging nerves. Alemtuzumab can cause dangerous or deadly side effects. Your doctor likely won’t put you on this until you’ve tried at least two other MS drugs first.

How you take it : By IV infusion once a day for 5 days, then 1 year later for 3 more days.

Side effects: You’ll need close monitoring, including regular blood tests for at least 5 years. This drug can lead to a rare and deadly bleeding condition. It also can affect your kidneys. About 1 in 3 users can get thyroid disease. You may have a serious reaction to the infusion. Most common side effects include:

  • Headache
  • Rash
  • Nausea
  • Fever

Natalizumab (Tysabri)

How it works: This antibody drug sticks to T cells and keeps them from reaching your brain and spinal cord and attacking the protective myelin. It’s usually prescribed if your relapsing MS is highly active or if you didn’t respond to other MS drugs.

How you take it: By infusion once every 28 days in an infusion clinic.

Side effects: It’s rare, but you can get a brain infection that can lead to disability or death. The symptoms at first may look like an MS relapse. Some people can be allergic to the drug. Common side effects include:


Ocrelizumab (Ocrevus)

How it works: The FDA approved it in 2017. It treats RRMS as well as primary progressive MS (PPMS). That’s when your condition steadily worsens without periods of relapses and remissions. Ocrelizumab is a monoclonal antibody and targets B cells that damage nerves. Studies show it may work better to lower relapses and to slow your MS than some interferon beta drugs.

How you take it: Two infusions 2 weeks apart, every 6 months.

Side effects: You should not take it if you have hepatitis B. As with other infusion drugs, you may get itchy skin, a rash, throat irritation, or an allergic reaction. Rarely, you can get a fatal brain infection.

Siponimod (Mayzent)

How it works: Siponimod is an immune system-modulating drug which enters the central nervous system and helps control inflammation. It helps your body’s lymph nodes retain certain white blood cells, stopping them from circulating throughout the body and into the central nervous system.

How you take it: You begin slowly and gradually increase your dosage. Initially starting with 0.25 mg for the first two days, then 0.50mg on day 3, 0.75 on day 4, up to 1.25 mg day 5 and up to 2mg as maintenance thereafter.  

Side effects: Possible side effects for those taking siponimod include disorders of the nervous system and wells as infections. The most common side effects include:

  • Diarrhea
  • Dizziness
  • Swelling in extremities
  • Arm or leg pain
  • Slowed heartrate
  • High blood pressure
  • Headaches

Mitoxantrone (Novantrone)

How it works: This is a former cancer drug that was approved for MS. It suppresses your immune system to lower the number of cells that attack your myelin. It’s the only drug besides Ocrevus that’s prescribed for a progressive form of MS, specifically secondary progressive MS. That’s when your condition worsens beyond RRMS.

How you take it: One infusion every 3 months, with up to 12 doses over 2-3 years.

Side effects: Because of safety worries, doctors usually prescribe this only if your MS is growing worse quickly and if other drugs haven’t helped. It can seriously affect your heart and may make you more likely to get blood cancer.

WebMD Medical Reference Reviewed by Christopher Melinosky on January 07, 2020



PubMed Health: “Interferon Beta-1a (By injection),” “Interferon Beta-1b.”

Medscape: “Multiple Sclerosis Medication.”

National Multiple Sclerosis Society (UK): “Plegridy,” “Disease Modifying Therapies for MS,” “Copaxone,” “Glatiramer acetate,” “Tecfidera,” “Lemtrada,” “Medications, “Types of MS.”

UpToDate: “Disease-modifying treatment of relapsing-remitting multiple sclerosis in adults.”

Drugs: “Teriflunomide and Its Mechanism of Action in Multiple Sclerosis.”

Multiple Sclerosis Society (UK): “Natalizumab.”

FDA: “FDA approves new drug to treat multiple sclerosis.”

Multiple Sclerosis Coalition: “The Use of Disease-Modifying Therapies in Multiple Sclerosis: Principles and Current Evidence.”

University of Utah College of Pharmacy: “Fingolimod (Gilenya) Drug Review.”

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