What is tocilizumab?

Tocilizumab (brand name Actemra) is a biologic medication used to treat rheumatoid arthritis (RA) and giant cell arteritis (GCA). It is the only biologic currently FDA-approved for GCA, where it allows patients to taper off prednisone faster and with fewer relapses.

Tocilizumab is an IL-6 receptor inhibitor. Interleukin-6 (IL-6) is one of the central inflammatory proteins in autoimmune disease — it drives joint inflammation in RA and blood vessel inflammation in GCA. By blocking the IL-6 receptor, tocilizumab turns down the inflammatory signal at a key control point.

How to take it

Tocilizumab is available in two forms:

Subcutaneous injection (at home):

For RA: 162 mg every other week, which may be increased to weekly based on response. Patients weighing 100 kg or more typically start at weekly dosing.
For GCA: 162 mg weekly (sometimes every other week), used alongside a steroid taper directed by your rheumatologist
Self-administered at home using a prefilled syringe or autoinjector after training in our office
Store in the refrigerator — remove and let it warm to room temperature for about 30 minutes before injecting
Rotate injection sites between the thigh and abdomen (at least 2 inches from the navel)

Intravenous infusion (in-office):

For RA: 4 mg/kg IV every 4 weeks, which may be increased to 8 mg/kg based on response (maximum 800 mg per infusion)
Given as a 1-hour IV infusion at our on-site infusion center
IV tocilizumab is not routinely used for GCA — the subcutaneous form is standard for that indication

Your rheumatologist will recommend which form based on your diagnosis, insurance coverage, and preference.

What to expect when starting

Many patients notice improvement within 4–6 weeks, though the full benefit often takes 3–6 months. In RA, tocilizumab is commonly used with methotrexate, but it is one of the few biologics shown to work well as monotherapy (without methotrexate) — an advantage if you can’t tolerate methotrexate.

For GCA, tocilizumab is typically started alongside prednisone. The goal is to use the biologic to control the disease while gradually tapering the steroid over several months, reducing prednisone’s long-term side effects.

Lab monitoring

Tocilizumab requires closer lab monitoring than most other biologics because it can affect your liver enzymes, blood counts, and cholesterol:

Liver function tests (ALT/AST) — checked every 4–8 weeks for the first 6 months, then every 3 months. Tocilizumab can raise liver enzymes, especially when combined with methotrexate.
Complete blood count (CBC) — monitors neutrophils (infection-fighting white blood cells) and platelets. Low counts may require dose adjustment.
Lipid panel — tocilizumab commonly raises cholesterol levels. This is usually managed with a statin if needed, not by stopping the medication.

Important: Tocilizumab blocks IL-6, which is the protein your body uses to generate CRP (a common inflammation marker) and fever. This means your CRP may stay low even during an active infection, and you may not develop a typical fever when sick. Don’t rely on “I don’t have a fever” as a sign that an infection isn’t serious — contact us if you feel unwell.

Side effects to watch for

Common:

Upper respiratory infections (cold symptoms, sinus congestion)
Headache
Injection site reactions (SC form) — redness or mild swelling, usually resolves quickly
Elevated cholesterol — monitored with blood work, treated if needed
Mild liver enzyme elevation — usually asymptomatic, monitored with blood work

Important — contact us if you experience:

Fever, chills, or any signs of infection — persistent cough, burning with urination, a wound that isn’t healing, or feeling generally unwell (remember, fever may be blunted)
Severe abdominal pain — tocilizumab may increase the risk of gastrointestinal perforation, particularly in patients with a history of diverticulitis. New-onset severe stomach pain needs urgent evaluation.
Unusual fatigue, dark urine, or yellowing of the skin/eyes — signs of liver injury
Easy bruising or bleeding — could indicate low platelets or neutrophils

Required screening before starting

Before your first dose, we will check:

TB screening (QuantiFERON blood test) — biologics can reactivate latent tuberculosis
Hepatitis B and C screening — to rule out chronic viral hepatitis
Baseline labs — CBC, metabolic panel, and liver function tests
Lipid panel — to establish your baseline cholesterol levels
Review of your vaccination history — certain vaccines should be given before starting
Diverticular disease history — we’ll ask about prior episodes to assess GI perforation risk

Things to avoid

Live vaccines — including live shingles vaccine (Zostavax), live nasal flu spray, and MMR. Inactivated vaccines (flu shot, COVID, Shingrix) are safe and recommended.
Other biologics — tocilizumab should not be taken with another biologic medication. Combining biologics significantly increases infection risk.
Don’t ignore infections — and remember that your usual warning signs (fever, elevated CRP) may be suppressed. When in doubt, call us.

About biosimilars

Actemra is the original brand name tocilizumab made by Genentech. Several biosimilar versions are now FDA-approved:

Tofidence (tocilizumab-bavi) — Biogen
Tyenne (tocilizumab-aazg) — Fresenius Kabi (available in both IV and SC)
Avtozma (tocilizumab-anoh) — Celltrion (available in both IV and SC)

A biosimilar is a biologic medication that has been rigorously tested and shown to have no clinically meaningful differences from the original product in safety, purity, or effectiveness. If your insurance plan covers or prefers a biosimilar, it is expected to work the same way. Your pharmacy or infusion center may dispense a biosimilar version — this is normal and does not represent a change in your treatment.

Frequently asked questions

How is tocilizumab different from a TNF inhibitor like Humira? TNF inhibitors block one specific inflammatory protein (TNF-alpha). Tocilizumab blocks IL-6, a different inflammatory pathway. In RA, it is often used when TNF inhibitors haven’t worked well enough, though it can also be used first-line. For GCA, tocilizumab is the preferred biologic — TNF inhibitors are not effective for that condition.

Can I take tocilizumab without methotrexate? Yes. Tocilizumab is one of the few biologics with strong data supporting its use as monotherapy in RA. If methotrexate causes side effects you can’t tolerate, tocilizumab alone is a well-supported option. That said, the combination often works better if you can tolerate both.

What if I miss a dose? For SC injections: take it as soon as you remember, then resume your regular schedule. For IV infusions: call us to reschedule as soon as possible. Try to stay within a week of your scheduled infusion date.

Can I take tocilizumab during pregnancy? Data on tocilizumab in pregnancy is limited. Current guidelines recommend stopping tocilizumab before a planned pregnancy when possible. If you’re thinking about starting a family, let us know well in advance so we can plan a transition to a pregnancy-compatible medication.

Will my cholesterol go back down if I stop tocilizumab? Yes — the cholesterol increase is a direct pharmacologic effect of IL-6 blockade, and it typically normalizes after stopping the medication. Whether the elevated cholesterol actually increases cardiovascular risk during treatment is still debated, but we monitor and treat it if needed.

This handout is for informational purposes and does not replace the advice of your physician. Always follow the specific instructions given to you by your rheumatologist. If you have questions or concerns about your medication, contact Synergy Rheumatology & Wellness.

Tocilizumab (Actemra): What You Need to Know